Alutrat is an effective and safe astringent, without any of the inconveniences of chlorydrates and other inorganic salts of aluminium.

On the basis of the foregoing studies we have looked for a substance and a non-toxic formulation that is in accordance with the requested dermatologic and cosmetic needs. Aluminium salts come up to our expectations better. We have excluded the most common inorganic salts, as chloride, hydroxychloride and sulphate because they are highly ionisable and consequently they form suddenly complexes with the epidermal proteins. So these salts are irritant for the skin and, above certain concentrations, they induce hydroxyadenitic inflammation. Besides, it has been shown some formulations precipitating proteins are not astringent. Other Authors demonstrated that the transmission el ectron microscopy of aluminium chloridrate (ACH)-treated sweat glands indicated that just as the duct leaves the epidermis, and passes through the stratum corneum to the skin surface, its lumen is completely filled with an electron-dense, amorphous materi al. This material, the counter part of the morin fluorescence with regard to relative location, is believed to be the plug, consisting of ACH or one of its reaction products, responsible for sweat gland inhibition. In contrast, untreated glands were patent and devoid of comparable material. Morin Fluorescence microscopy of those g lands revealed that aluminium was present within the duct, generally as a solid mass at the level of the stratum corneum.

Occasionally, some aluminium fluorescence was also observed in the duct at the level of the upper epidermis. Fluorescence was never observed in control (untreated) glands. Last we have seen a fabrics corrosion where they touched the formulation. In partic ular cellulose fabrics, like rayon and cotton, are exposed to this attack.

Our experience and others on antiperspirant formulations led to the synthesis of an experimentally highly competing and openly less toxic salt.

It is an organic salt, less absorbed by the skin but with a high power in modifying sweat gland activity. It operates without the typical "impact" action of equiactive inorganic formulations. We refer to hydroxyaluminium citrate, Alutrat, that s hows all advantages of aluminium derivatives, but does not produce any significant toxic effect, not even bland.

Employment possibilities
The hydroxyaluminium citrate (Alutrat) not aggressive action is used for antiperspirant formulations (sprays, podalic detergents, skin dusting powders) for face astringent lotions (tonics, masks, after-shave lotions), and for special hygiene detergents.

According to experimental and clinic researches we came to the conclusion that hydroxyaluminium citrate shows a meaningful astringent action after sufficiently prolonged skin application, either from the physiological point of view, or for its capability of eliciting a dose-dependent effect.