80 JOURNAL OF COSMETIC SCIENCE
Assume that a formulator has narrowed down the potential replacements to only a few
candidates based on their experience, supply, and cost guidelines. However, in reality, the
number of potential options could be significantly higher. It is unlikely that any single
emollient among these candidates on its own would be a perfect match to dimethicones.
The number of potential binary or ternary mixtures that could match the performance
of dimethicones can easily become very large. It is important to note that no formulator
would explore all possible candidates, as it would be extremely time-consuming and
expensive. However, it is highly likely that the ideal natural-based candidate to replace
dimethicones is present within these possible mixtures. Therefore, it is evident that one
needs an alternative method to capture potential candidates.
An effective approach to overcome this challenge is to leverage digitization, scientific
modeling, and the benefits derived from enhanced computing power. One such option
is Emollient Maestro12, a digital service that can be utilized to identify natural-based
candidates as replacements for a wide range of synthetic silicones, including D5 and
dimethicones with viscosities ranging from 1 to 200 cSt, mineral oils, and hydrocarbon-
based emollients such as isododecane, isohexadecane, squalene, and many more.
The algorithm powering Emollient Maestro employs prediction and optimization models
that theoretically explore all possible emollient combinations and then return the best ones
that match a given synthetic dimethicone benchmark. This service offers a highly efficient,
quick, and cost-effective solution for formulators to identify potential replacements for
dimethicones and other synthetic emollients.
Figure 2 illustrates the emollient-level performance profiles of dimethicone 5 cSt, which is
commonly used in skin care emulsions for its sensory benefits, and an optimized natural-
based emollient mixture of dicaprylyl carbonate, dicaprylyl ether, and undecane/tridecane
(ratio 1.7:3.2:1) obtained from Emollient Maestro. The left panel in Figure 2 shows an
overlapping physico-chemical profile of the silicone (which was experimentally measured)
versus the natural-based emollient mixture (which was predicted). In this panel, various
properties that formulators consider when selecting a new ingredient, i.e., viscosity,
Figure 2. Physico-chemical (left) and monadic sensory (right) comparisons between dimethicone 5 cst
(experimentally measured) and a natural-based emollient combination recommended by Emollient Maestro
(prediction), exhibiting a good agreement at the emollient level.

81 Silicone Alternative Solutions in Personal Care
spreading value, density, refractive index, surface tension, interfacial tension (polarity), and
equivalent alkane carbon number are compared.
The right panel of Figure 2 shows an overlapping sensory profile of the silicone versus the
natural-based emollient mixture. The sensory profile of dimethicone was assessed using
trained panelists and is represented on a monadic scale, while the sensory profile of the
natural-based emollient was theoretically estimated using Emollient Maestro. It is worth
noting that Figure 2 demonstrates a good agreement between both the physico-chemical
and sensory profiles of dimethicone 5 cSt and the natural-based emollient mixture proposed
by Emollient Maestro.
As previously discussed, the unique structures of dimethicones mean that they are used
in personal care formulations for a secondary reason, namely as anti-whitening agents.
Therefore, removing dimethicones can lead to a strong undesired whitening effect on
the skin upon application. This is caused by the formation of foam due to the presence
of ingredients such as fatty alcohols and biopolymers, which are present in significant
quantities in cosmetic emulsions. Small amounts of dimethicones can reduce the foaming
and significantly reduce the whitening effect.
By utilizing solutions from Emollient Maestro and adjusting selected galenic ingredients,
formulators can develop a truly silicone-free skin care formulation with the same
performance. Through experimentation with various combinations in a reference
formulation, the following combinations can prove to be effective. Firstly, using mono- and
diglyceride-based waxes as an alternative to fatty alcohols offers advantages in minimizing
whitening effects. In addition, incorporating biopolymers such as alginate, when cross-
linked with CaCl
2 ,can produce particles that further reduce the whitening effect while
providing a pleasant and non-sticky feel on the skin.
Furthermore, it is crucial to carefully select emulsifiers that have a neutral sensory
impact. This means opting for emulsifiers that do not dictate or negatively influence
the sensory characteristics of the final formulation. By choosing emulsifiers with a
neutral sensory profile, the desired sensory attributes of the silicone-free formulation are
maintained.
By employing these strategies and combinations, formulators can successfully develop a
silicone-free skin care formulation that meets the desired sensory and performance criteria.
The effectiveness of this approach has been tested on a benchmark day care face cream13
that would typically contain 10% of dimethicone 5 cSt, commonly found in the market.
Figure 3 depicts a sensory comparison between the formulation containing dimethicone 5
cSt and the formulation containing emollient mixtures predicted by Emollient Maestro.
The results of the comparison revealed that the natural-based formulations exhibited an
almost identical sensory profile during application of the day care face cream as the one
containing dimethicone. This rigorous evaluation process allows an estimation of the
sensory attributes of the silicone-free formulation in a standardized manner, ensuring
reliable and consistent results.
A standardized assessment allows an objective estimation and comparison of the whitening
effects of the formulations, providing valuable insights into the performance of the natural-
based alternative. The results indicate that both the formulation containing dimethicone
5 cSt and the natural-based alternative effectively minimize the whitening effect typically
associated with the absence of dimethicone.