WO1996005804A2

WO1996005804A2 - Preparation for cosmetic and/or pharmaceutic use, including active carbon and scattering substances

Info

Publication number: WO1996005804A2
Application number: PCT/IT1995/000137
Authority: WO
Inventors: Carlo Alfredo Graziani; Enzo Melis
Original assignee: Carlo Alfredo Graziani; Enzo Melis
Priority date: 1994-08-25
Filing date: 1995-08-08
Publication date: 1996-02-29
Also published as: AU3353295A; WO1996005804A3; ITRM940545A0; ITRM940545A1; IT1274150B; EP0777461A2

Abstract

A preparation for cosmetic or pharmaceutical use comprises active carbon (1) in granular form, mixed with talcum (2) and starch (3) also in granular form. The granules of talcum (2) and starch (3) have dimensions smaller than the granules of the active carbon (1) and define an intermediate layer between the active carbon (1) and the surface (4) to be treated, e.g. the skin of a human body. The preparation has a very high adsorbent power (about thousand times that of talcum) in addition to its optimum absorbent characteristic. When used as deodorant, it does not cover the odours, but adsorbs and eliminates the bacteria, which are the cause of the same odours, rendering useless any bactericide on the skin.

Description

PREPARATION FOR COSMETIC AND/OR PHARMACEUTIC USE, INCLUDING ACTIVE CARBON AND SCATTERING SUBSTANCES

Background of the Invention

This invention relates to the field of preparations for cosmetic or pharmaceutical use, comprising active principles scattered in substances which are substantially inert, for the purpose of acting as solvent element or scattering element.

In particular, among these preparations, those in the form of strewing powders, having a basis of talcum, starch or kaolin, are very diffused; all these strewing powders having deodorising, absorbing and der aprotective effects.

Some of these strewing powders, as the talcum, are more active with fats, while others, as kaolin, better absorb hydrophilic substances and, for this reason, are often mixed together, in various percentages and combinations. In addition, it is also known the use of anti-oxidizers, as tocopherol, having a deodorising effect. All these products, for their average composition, have bacteriological or bactericidal action, a certain absorbing capacity and a simple effect of aseptic covering odours.

It is well known to any person skilled in the art that, among the substances very effective as adsorbent and deodorant, the active carbon is certainly the one which has the maximum potentiality of removing undesired gases and liquids.

In particular the active carbon, due to its porous structure and its wide specific surface (about 1.000 sq.m./g), can be considered as an air container. However, it is also true that the effectiveness of active carbon is very reduced by the fact that the active carbon can not be directly applied to sensitive surfaces, and in particular to body skin, due to its staining power and to the high dehydration which would cause on cutis below. Another very important characteristic of active carbon is its good capacity to adsorb bacteria and viruses.

Also for the foregoing reasons, the improvement of working forms and marketing of active carbon is an essential problem for the development of preparations which must be always more versatile and with a high adsorbent and deodorant power. cjιιιτιmaτ-γ nf the Invention

Scope of the present invention is to improve the characteristics of known products and to optimize the effectiveness of active carbon produced in granular form, avoiding the aforementioned inconveniences and allowing the direct use on the skin.

In accordance with this scope, the proposed preparation for cosmetic and/or pharmaceutic use comprises a mixture of granular active carbon with solvent and scattering substances which have dimensions smaller that the active carbon in order to partially cover the external surface of said active carbon. In this manner the preparation is compatible with the body skin or any other sensitive surface, without decreasing the adsorbent capacity of gases and liquids.

The main advantage of this preparation consists essentially in its very high adsorbent power (about thousand times that of talcum) in addition to its optimum absorbent characteristic.

A second advantage is represented by the active carbon in the preparation; in fact it does not cover the odours, but adsorbs and eliminates the bacteria, which are the cause of the same odours, rendering useless any bactericide on the skin.

In addition to the foregoing, the wide specific surface of active carbon aids the gaseous exchanges between skin and preparation and acts as water-gas exchanger between skin and air, aiding evaporation of perspiration and allowing also an effective dermatic insulation.

Another advantage of the preparation according to the present invention is its lubricating and protective effect due to the mixture of active carbon covered by starch, talcum or equivalent powders, and also that the active carbon maintains all its effectiveness without staining or attaching to fabric. Brief description of the drawings These and other advantages of the present invention will be made clear from the following description of a preferred embodiment given by way of a non-limiting example and with reference to the accompanying drawings, wherein:

FIG. 1 schematically shows the kind of exchange which happens between the skin and a preparation according to the present invention;

FIG. 2 schematically shows the existing interaction between the active carbon and the covering powder of a preparation according to the present invention; FIG. 3 schematically shows the model of sliding on the skin of particles of a preparation according to the present invention;

FIG. 4 shows a granule of active carbon without cover, enlarged onehundred times; FIG. 5 shows a granule of active carbon covered by starch, enlarged onehundred times; and

FIG. 6 shows a granule of active carbon covered by microparticles of talcum, enlarged onethousand times. Description of a preferred embodiment With reference to FIG. 1, a preparation according to the present invention comprises active carbon 1 in granular form, mixed with starch particles 3 and talcum particles 2, which are considered solvent and scattering substances.

This preparation can be used as strewing powder to be applied on the skin 4 of the human body as refreshing or deodorant. In such a case a preferred ratio, in weight, of talcum, starch and active carbon is 84:14:2 respectively.

For preparing the strewing powder, first of all a homogeneous mixture (1:1) of starch and active carbon is formed and treated in humidity room at 70 Celsius degree for 15 minutes; then the remaining starch is added to the mixture, to reach the above mentioned ratio, according to the method of geometrical dilutions. Further, the mixture is heated in oven at 80 Celsius degree for 10 minutes, with the effect to swell the starch particles and improve their link with the active carbon. The obtained mixture is then integrated with talcum. In the realized preferred form, it has been used active carbon in grains of the kind "Carbo Declorans" in powder of 170 mesh, soluble rise starch and base talcum, both having granules of substantially spherical form.

With the above mentioned ratio and dimensions it has been obtained a powder on which some feeble electric interactions occur between the covering particles and the active carbon; such electric interactions helping the desired partial covering of active carbon and originating a physical absorption on surface of active carbon. This situation, shown in FIG. 1, permits to the active carbon 1 to act on the skin 4 without directly adhering thereon, due to the partial interposition of starch particles 3 which on a whole constitute a mobile covering layer. More in particular, the spherical form and the suitable dimensions of covering particles avoid the early saturation of active carbon and maintain a feeble link which helps the mobility of the covering layer and the progressive adsorption of substances to eliminate. Such substances, in fact, being smaller than the covering particles 2 and 3, and having the capability to better link with the active carbon, are adsorbed by the internal porosity of the active carbon grains, up to, as limit condition with the active surface saturated, to substitute the same covering particles 2 and 3. Therefore, the covering layer of particles 2 and 3 permits three kinds of exchange between active carbon and skin: a) direct exchange in correspondence of the free grain surface facing the skin; b) physical adsorption with formation of a plurality of layers of substances to eliminate, which link to the active carbon; and c) exchange mechanism between the covering particles and the substance to eliminate, which depends by the link force of adsorbed particle.

Moreover, as further advantage of this preparation, the uniform distribution of solid-solid solution permits the forming of a dermaprotective layer, insulating and absorbing, which according to the model shown in FIG. 3 acts as a small cushion, through which the gaseous exchanges with the skin can happen without exposing the same skin to risks of stains or excesses of dehydration. The preparation according to the present invention can be also be prepared combining with the active carbon other substances like kaolin or proteinic fractions either animal or vegetable.

It is clear that the choice of using the active carbon in granular form as strewing powder is to be considered solely as one of the plurality of possible uses, particularly useful for certain applications, for example as foot deodorant, provided however that other different forms, as paste, gel or ointment may also be considered, without going thereby beyond the scope of the present invention.

Claims

1. Preparation for cosmetic and/or phar aceutic use comprising active carbon (1) in granular form, characterised in that said active carbon (1) is mixed with starch (3) and talcum (2) which cover the external surface of said active carbon (1) and define an intermediate layer between said active carbon (1) and the surface (4) to be treated.

2. Preparation according to claim 1, characterised in that ratio, in weight, of said active carbon (1), said starch (3) and said talcum (2) is 2:14:84.

3. Preparation according to claim 1, characterised in that said active carbon is constituted by Carbo Decolorans of 170 mesh, said starch (3) is constituted by powder of rise starch and said talcum (2) is constituted by base talcum.

4. Preparation according to claim 1, characterised in that said starch (3) and said talcum (2) are in granular form and have dimensions smaller that the granules of said active carbon (1) .

5. Preparation according to claim 1, characterised in that said starch (3) and said talcum (2) are in granular form, the granules of said starch (3) and said talcum (2) having dimensions comprised between the dimension of a granule of said active carbon (1) and the dimension of the porosity of this latter.

6. Preparation according to claim 1, characterised in that said starch (3) and said talcum (2) have a substantially spherical form.

7. A deodorant comprising active carbon (1) in granular form, characterised in that said active carbon (1) is mixed with at least a solvent and scattering substance which covers the external surface of said active carbon (1) and defines an intermediate layer between said active carbon (1) and the surface (4) to be treated.

8. A deodorant according to claim 7, characterized in that said solvent and scattering substance comprises talcum (2).

9. A deodorant according to claim 8, characterized in that said talcum (2) is in granular form having dimensions smaller that the granules of said active carbon (1).

10. A deodorant according to claim 8, characterized in that the granules of said talcum (2) have dimensions comprised between the dimension of a granule of said active carbon (1) and the dimension of the porosity of this latter.

11. A deodorant according to claim 8, characterized in that starch (3) is mixed with said talcum (2) to form a strewing powder.

12. A deodorant according to claim 7, characterized in that said solvent and scattering substance comprises kaolin.

13. A deodorant according to claim 7, characterized in that said solvent and scattering substance comprises proteinic fractions.