STABILISED SILICATE COMPOSITIONS AND THEIR USE AS ANTIPERSPIRANT COMPOSITIONS

1 . An antiperspirant composition comprising a stabilised silicate composition which comprises polysilicic acids, wherein the antiperspirant composition has a pH between 2.5 and 5.0 and wherein the application of the antiperspirant composition to a subject causes a pH shift in the composition that induces growth of the polysilicic acids to form a gel thereby providing an antiperspirant active ingredient.

2 . (canceled)

3 . The antiperspirant composition of claim 1 , wherein the pH shift is to a pH of above 5 and below 8.

4 . The antiperspirant composition of claim 1 , wherein the pH shift occurs in skin pores and causes production of the silicate gel in the pores.

5 . The antiperspirant composition of claim 1 , wherein the pH of the composition is between pH 3.0 and 5.0.

6 . The antiperspirant composition of claim 1 , wherein the stabilised silicate is stabilised by at least one growth retardant.

7 . The antiperspirant composition of claim 6 , wherein the growth retardant is a carboxylic acid, an amino acid, an inorganic anion, a polyol, saccharide and/or a quaternary ammonium cation.

8 . The antiperspirant composition of claim 7 , wherein the carboxylic acid is a C 2-10 dicarboxylic acid, the amino acid is aspartic acid, the polyol is a monomeric polyol, polyalkylene glycol, or a saccharide, and the quaternary ammonium cation is choline.

9 . The antiperspirant composition of claim 1 , wherein the stabilised polysilicic acid particles are incorporated into an antiperspirant composition or a cosmetic formulation comprising one or more polyalkylene glycols.

10 . (canceled)

11 . The antiperspirant composition of claim 1 , wherein the stabilised polysilicic acid particles are poorly condensed as determined in an in vitro dissolution assay in which at least 25%, of the composition dissolves in 24 hours in HEPES buffer.

12 . The antiperspirant composition of claim 11 , wherein the in vitro dissolution assay is a molybdic acid assay for determining the soluble silicic acid fraction.

13 . The antiperspirant composition of claim 1 , wherein the stabilised silicate composition comprises a multivalent cation selected from the group of Ca 2+ , Mg 2+ , CU 2+ , Fe 3+ and Zn 2+ .

14 . The antiperspirant composition of claim 13 , wherein the multivalent cation is added to provide the stabilised silicate composition with a final concentration between 0.01 M and 1.0 M, and preferably a final concentration between 0.05 M and 0.5 M.

15 . The antiperspirant composition of claim 1 , wherein the stabilised silicate composition is stabilised by a non-aqueous solvent.

16 . (canceled)

17 . The antiperspirant composition of claim 15 , wherein the non-aqueous solvent is added between 10 and 70% v/v.

18 . The antiperspirant composition of claim 1 , wherein the composition comprises at least one of an additional antiperspirant active agent, a deodorant, a volatile or non-volatile oil, silicone and hydrocarbon-based emollient oils, a suspension agent, a perfume or fragrance, an organic powder and/or a water-immiscible organic liquid phase and at least one agent for structuring said phase.

19 . (canceled)

20 . The antiperspirant composition of claim 1 , wherein the composition is conditioned such that it can be contained in an aerosol device, a pump-dispenser bottle, a roll-on, a device equipped with a perforated wall, or a wand (stick).

21 . (canceled)

22 . A cosmetic process for treating human perspiration, comprising applying to the surface of the skin of a human subject an effective amount of an antiperspirant composition of claim 1 , wherein the application of the antiperspirant composition to the subject causes a pH shift in the composition that induces growth of the polysilicic acids to form a gel thereby providing an antiperspirant active ingredient.

23 . The cosmetic process of claim 22 , wherein the antiperspirant composition is applied for treating human body odour.

24 . A method of treating of a medical condition characterised by excessive perspiration, the method comprising applying to the surface of the skin of a subject an effective amount of an antiperspirant composition of claim 1 , wherein the application of the antiperspirant composition to the subject causes a pH shift in the composition that induces growth of the polysilicic acids to form a gel thereby providing an antiperspirant active ingredient.

25 . The method of treatment of claim 24 , wherein the medical condition is hyperhidrosis.

26 . The method of treatment of claim 25 , wherein the hyperhidrosis is primary or focal hyperhidrosis or secondary hyperhidrosis.

27 . The method of treatment of claim 26 , wherein the excessive perspiration is caused by acromegaly, anxiety disorders, cancer, carcinoid syndrome, endocarditis, heart attack, hyperthyroidism, substance abuse, obesity, diabetes, heart disease, HIV/AIDS, hyperthyroidism, lung disease, medications, menopause, Parkinson's disease, pheochromocytoma, spinal cord injury, stroke, stress, tuberculosis, fever or infection.

28 . (canceled)

29 . A method for producing stabilised polysilicic acids, the method comprising:

(a) preparing an alkaline silicate solution having a pH≧9.5;

(b) optionally adding a growth retardant to the alkaline silicate solution;

(c) lowering the pH to ≦4.0 by adding an acid to form a composition comprising polysilicic acids;

(d) optionally adding a multivalent cation and/or a growth retardant;

(e) raising the pH of the composition to a physiological acceptable pH by adding a base, thereby forming the stabilised composition comprising polysilicic acids;

(f) optionally adding a growth retardant capable of increasing the stability of the composition;

(g) optionally adding a non-aqueous solvent capable of increasing the stability of the composition; and

(h) optionally incorporating into an antiperspirant formulation or a cosmetic formulation for application to a subject.

30 - 51 . (canceled)

52 . A method for producing an antiperspirant composition which method comprises having produced a stabilised silicate composition according to the method of claim 29 , the further step of formulating the stabilised colloidal silicate composition with one or more additional components to produce an antiperspirant composition.

53 - 55 . (canceled)

56 . A stabilised silicate composition as obtainable by the method of claim 29 .

57 . An antiperspirant composition comprising a stabilised silicate composition as obtainable by the method of claim 52 .