Aluminium chlorhydrate

Antiperspirant. Aerosol form using butane-propane blend as propellant, and packed in lacquer-lined aluminium cans. Should contain an active antiperspirant at an effective dosage (e.g. aluminium chlorhydrate). 

Thoroughly disperse the bentonite and activated aluminium chlorhydrate in the isopropyl myristate and DC 344 fluid, using a high-shear mixer. Add the DC 1401 and the fragrance, mixing well. Fill into internally lacquered aluminium aerosols, as shown above. 

The organoleptic stability of an ingredient depends on a combination of two factors its sensory characteristics and its chemical stability. The latter, of course, is determined by the nature of the product base. Antiperspirant formulations are acidic because of partial hydrolysis of the active antiperspirant agents, such as aluminium chlorhydrate (equation 1). It is an inorganic salt that consists essentially of complex aluminium chloride described empirically as [Al2(OH)5] .nCl. The complex is polymeric and loosely hydrated. 

Andy Roche, Reheis, for information on the partial hydrolysis of aluminium chlorhydrate. 

Clear antiperspirants have become popular because they leave no visible residue.They are not always formulated through a microemulsion route. Clear sticks can be based on dibenzylidene sorbitol acetal (DBSA) gelling agent and zirconium or glycine-complexed aluminum chlorhydrate antiperspirant actives that are soluble in propylene glycol without water. An alternative route is to closely match the refractive indices of the oil and water phases so a clear product (not a microemulsion) results for an antiperspirant gel [20,23]. Clear deodorant sticks with the active ingredient triclosan can be solidified with sodium stearate, which is incompatible with antiperspirant active ingredients (aluminium chlorhydrates). 

The Stephen s method allows the reduction of nitriles by stannous chloride in acid medium. If the amine chlorhydrate initially formed is hydrolyzed, the corresponding aldehyde is obtained (37, 91). Harington and Moggridge (37) have reduced 4-methyl-5-cyanothiazole by this method (Scheme 23). However, Robba and Le Guen (91) did not obtain the expected products with 4.5-dicyanothiazole and 2-methyl-4,5-dicyanothiazole. These compounds have been reduced with diisobutyl-aluminium hydride with very low yields (3 to 6%) (Scheme 24). In other conditions the reaction gives a thiazole nitrile aldehyde with the same yield as that of the dialdehyde. 

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