Rhelogical approach to a natural formulation
Concentrated emulsion, diluted in water, can be added in a cold process with a new thickening agent: a mixture of polymers from natural sources, well known in food industries.
A wide range of additional ingredients (oils, hydrophilic and lipophilic actives, perfumes and preservatives) were added to the gel achieving stable products, whit a good texture and great skin feel.
In this study the possibility of green final product formulation was investigated, with the methodology of concentrated emulsion (1) developed by our company (ResConcept PGF GREEN). A systematic inquiry was set up on natural (or from natural sources) thickening agents concluding that choosing the “green way” means often to obtain weak rheological and sensorial performances. Starting from studies (2,3,4) performed in food field, we selected a mixture Guar/Xanthan gum: rheologists know very well the synergistic effect of those two polymer in thickening aqueous solutions in cold processing. (Figure 1)
From hydroxypropyl-guar (G) and Xanthan gum (X) we prepared different mixtures changing the relative amount of the two polymers and finally we selected an optimized mix (Resil GX).
Viscosity of the different mix has been tested at 25°C with computer-aided viscosimeter Rheomat RM 180 from Rheometric Scientific, equipped with (Figure 2) Cuvette geometry with different coassial cylinders.
All measurements were made in triplicate and all samples were equilibrated in the measuri ...