GB2139496A - Antiperspirant stick with low staining potential - Google Patents

Abstract

An antiperspirant stick composition comprising a waxy material in which is suspended active antiperspirant material in particulate form, contains sufficient water-soluble emollient to avoid the waxy feel and to minimize the "drag". The preferred emollient is dimethyl isosorbide.

Description

SPECIFICATION Antiperspirant stick with low staining potential This invention relates to an antiperspirant stick composition. More particularly, it concerns a stick of this character containing a water-soluble emollient and especially containing dimethyl isosorbide.

Antiperspirant preparations in stick form are increasingly becoming one of the more popular modes of applying active antiperspirant materials. In developing products of this character, several criteria for consumer acceptability must be borne in mind if the product is to be marketed successfully.

Among these is the agreeable feel that this product must have when it is applied to the skin. A second important characteristic is the low potential for staining clothing that the product should exhibit.

The staining potential of antiperspirant products is a long standing problem that the industry has had to deal with. This has generally been defined in terms of the difficulty or ease with which a stain made by an antiperspirant on a fabric may be removed in a standarized laundering test.

One of the forms of antiperspirant sticks that has gained a fair degree of acceptance is the so-called suspension type product. In this type of product, a waxy material e.g. stearyl alcohol is used as a vehicle in which the active antiperspirant material is suspended in solid particulate form, usually as a powder.

These products are prepared by heating the vehicle to its molten state and then stirring in the solid particulate antiperspirant. The molten product is then poured into molds and allowed to cool.

A product prepared as described above has the minimal requirements for an antiperspirant stick and is hardly acceptable for commercial purposes. Thus, for example, such a product has an uncomfortable waxy feel when applied to the skin. Furthermore, there is a "drag" in a stick of this kind as it passes over the skin and hair in the regions at which they are employed.

In an effort to overcome these problems, it has been suggested in the prior art to incorporate a water-insoluble emollient in the suspension type antiperspirant stick composition. One type of material that has been highly recommended for this purpose is the so-called volatile silicones e.g. Cyclomethicone.

Although the use of the volatile silicones goes a long way in improving the waxy feel and "drag" characteristics noted above, this has been largely done at the expense of increasing the staining potential of these products. It has now been found, however, that the waxy feel and drag can be eliminated without increasing the staining potential of these antiperspirant sticks if essentially all of the volatile silicone is replaced with a water-soluble emollient like dimethyl isosorbide. Furthermore, antiperspirant sticks of the present invention are non-tacky effective products. Moreover, since the dimethyl isosorbide is neither a primary irritant nor a skin sensitizer, the present antiperspirant sticks have a low potential for being irritating.

It is accordingly a primary object of the present invention to provide an antiperspirant stick composition that does not have a waxy feel or exhibit drag characteristics but which still has a low potential for staining.

It is also a further object of the present invention to provide antiperspirant sticks of the aforesaid character which are non-tacky and which are effective antiperspirants.

It is still a further object of the present invention to provide antiperspirant sticks having the aforesaid characteristics which also have a low potential for irritation.

Other and more detailed objects of this invention will be apparent from the following description and claims.

As indicated above, an essential feature of the present invention is the incorporation of a watersoluble emollient and, particularly, the incorporation of dimethyl isosorbide in an antiperspirant stick composition. Dimethyl isosorbide is a water-soluble, high boiling liquid that is non-volatile and nongreasy. It is practically inert and miscible with many organic materials. Because of this, it can be readily incorporated as a component of an antiperspirant stick composition without fear of interacting with the other components of the stick. This material has the structural formula

and is available commercially.

Although dimethyl isosorbide is the preferred water-soluble emollient that is useful for the purposes of the present invention, other water-soluble emollients may also be employed. By way of illustrating such other water-soluble emollients, the following may be mentioned: alkylene polyhydric alcohols such as propylene glycol, ethylene glycol, diethylene glycol, butylene glycol, several other glycols, such as the higher polyethylene glycols, water soiuble compounds of the general formula::

wherein a has an average value of from 2 to 23 and b has an average value of from 3 to 45. (Ucons of the HB series manufactured by Union Carbide), Randem copolymers prepared by the redaction of ethylene oxide and propylene oxide in various molar proportions (Ucon of the 45 H series, Union Carbide), block copolymers known as Pluronics, the polyoxypropylene, polyoxyethylene thereof the long chain fatty alcohol e.g.

in which x and y are whole numbers; R is a long chain fatty alcohol moiety (e.g. cetyl, myristyl, stearyl).

The value of x can range from 3 to 10 and the value of y can range from 2 to 50. Procetyl AWS (Exoda).

The water-soluble emollients and especially dimethyl isosorbide will ordinarily constitute a very significant portion of the antiperspirant stick products of this invention. Generally, it will constitute from about 1 5% or 20% to about 80.0% by weight based on the total weight of the stick composition. In the preferred cases, this range will be from about 35.0% or 40% to about 50% or 60.0% on the same weight basis.

The remainder of the antiperspirant stick composition of this invention may be constituted as an otherwise conventional antiperspirant stick composition of the suspension type. Thus, the backbone of the antiperspirant sticks of the present invention may comprise a low melting point waxy material that is a waxy material having a melting point of from about 1000F to 1500 F.

Typical suitable low melting point waxes are fatty acids containing from about 8 to about 22 carbon atoms, fatty alcohols containing from about 8 to about 22 carbon atoms, silicone waxes and glycerol monostearate. Especially useful materials of this type are the Cs to C22 fatty acids and C8 to C22 fatty alcohols. By way of example, the following may be mentioned: cetyl alcohol, stearyl alcohol, myristyl alcohol, lauryl alcohol and behenyl alcohol. However, the preferred low melting point wax is stearyl alcohol.

The quantity of the low melting point wax that may be contained in the present antiperspirant stick compositions may also vary somewhat. Ordinarily, this will comprise from about 8.0% to about 35.0% by weight based on the total weight of the composition and preferably from about 16.0% to about 27.0% by weight.

A quantity of water insoluble high melting wax may also be incorporated in the present antiperspirant stick compositions to help provide the basic structure of the stick. Suitable waxes for this purpose are water-insoluble waxes having a melting point of from about 1 500F to about 21 50F.

Examples of suitable waxes are carnaubau, beeswax, spermaceti, bayberry, condelila, montan, ozokerite, ceresin, paraffin, synthetic waxes and microcrystalline waxes and mixtures thereof. These may constitute from about 5% to about 1 0% by weight based on the total weight of the stick composition. However, in the preferred sticks, this will comprise from about 2.0% to about 6.0% on the same weight basis.

For the purpose of obtaining and maintaining a more homogeneous distribution of the powdered active antiperspirant material in the stick composition of this invention, a so-called "waxy gelling agent" may be employed. These are described in some detail in the U.S. Patent 4,229,432 columns 2 and 3 which are incorporated herein by way of reference and includes such materials as FT-300 wax, Paraffin Wax 133 /135 95 White Wax, Victory White Wax and Multiwax 18WM and mixtures thereof. This may generally comprise from about 0.5% to about 10.0% by weight of the stick based on its total weight with the preferred quantities being in the range of from about 2% to about 5% on the same weight basis.

The principai active ingredient in the antiperspirant stick composition of this invention is of course the antiperspirant material. This will ordinarily take the form of an astringent aluminum or zirconium compound or mixtures thereof; that is, mixtures or complexes of aluminum compounds or mixtures of zirconium compounds or mixtures of aluminum compounds with zirconium compounds. Usually, the aluminum or zirconium compounds will be in form of astringent salts. Typical antiperspirant actives include impalpable aluminum chlorhydroxide and aluminum hydroxybromide, aluminum chloride, aluminum zirconium polychlorohydrate complexes as well as the antiperspirant actives disclosed in Patent 3,792,068 issued February 1 2, 1 974 to Luedders et al.

This Luedders et al patent discloses a complex of aluminum, zirconium and amino acid by: A. Co-dissolving in water (1) one part Ai2(OH)6~mXm, wherein X is an anion selected from the group consisting of chloride, bromide and iodide and m is a number from about 0.8 to about 1.2; (2) n parts ZrY wherein Y is an anion selected from the group consisting of --O(OH)CI and OCI2, and where n has a value of from about 0.16 to about 1.2; (3) p parts neutral amino acid selected from the group consisting of glycine, dl-tryptophane, dlbeta-phenylalanine, dl-valine, di-methionine and beta-alanine, and where p has a value of from about 0.06 to about 0.53; B. Co-drying the resultant mixture at a temperature of from about 1 000C to about 2300C to a moisture level of from about 0.5% to about 15% by weight; and C.Comminuting the resuitant dried inorganic-organic antiperspirant complex into the form of an impalpable powder.

The preferred aluminum compound for preparation of the Luedders et al complex is aluminum chlorhydroxide of the formula Al2(OH)5C12H2O. The preferred zirconium compound for preparation of the Luedders et al complex is zirconyl hydroxychloride having the formula ZrO(OH)CI3H2O. The preferred amino acid for preparing the Luedders et al complex is glycine of the formula CH2(NH2)COOH.

Salts of such amino acids can also be employed in such antiperspirant complexes.

The aluminum zirconium polychlorohydrate complexes that may be incorporated in the stick compositions of the present invention may be described by the general formula:

wherein: (a) x is a number from 2 to 10; (b) Z is a number from 3 to 8; (c) y equals (3x + 4) - (d) the sum of y + Z is a number from 10 to 34; (e) m is a number from 0 to 12; (f) n is a nurnberfrom 0 to 3 y ordinarily will have a value of from about 5 to about 29.

As will be clear from Formula IV, the glycine may be bound in the complex or it may be absent.

The presence or absence of the glycine in the complex will determine the amount of unbound glycine or other buffer that may be incorporated in the composition to increase the pH to a level of from about 2.5 to about 4.5 or the preferred pH of from about 2.8 to about 3.8.

A number of aluminum zirconium polychlorohydrate complexes are known in the prior art which are useful for the present purposes. By way of example, the following may be mentioned along with their empirical formulas: aluminum zirconium tetrachlorohydrate (Al4Zr(OH)12CI4); aluminum zirconium tetrachlorohydrate glycine (Wickenol #E369) (Al4Zr(OH)12CI4 - NH2CH2COOH); aluminum zirconium trichlorohydrate (Al4Zr(OH)13CI3; aluminum zirconium trichlorohydrate glycine (Al4Zr(OH)13C13. NH2CH2COOH); aluminum zirconium pentachlorohydrate (Al 10Zr(OH)29C15); aluminum zirconium pentachlorohydrate glycine (Al10Zr(OH)29CI5 NH2CH2COOH); aluminum zirconium octachlorohydrate (Al6Zr(OH)14Cla); aluminum zirconium octachlorohydrate glycine (Al6Zr(OH)14C18. NH2CH2COOH). The aluminum zirconium polychlorohydrate complex can be mixed individually with the ACH and AlCi3 6H2O in solution or powder form or in various combinations thereof.

The OTC Panel on antiperspirants of the Food and Drug Administration has adopted certain nomenclature and specifications for various aluminum zirconium polychlorohydrates that are useful in the present invention. These are set out in Table A below: TABLE A Panel Adopted Metal-Halide Al/Zr Nomenclature Ratio Range Ratio Range Aluminum zirconium 2.1 down to but not 2.0 up to but not trichlorohydrate including 1.5:1 including 6.0:1 Aluminum zirconium 1.5 down to and 2.0 up to but not tetrachlorohydrate including 0.9:1 including 6.0:1 Aluminum zirconium 2.1 down to but not 6.0 up to and pentachlorohydrate including 1.5:1 including 10.0:1 Aluminum zirconium 1.5 down to and 6.0 up to and octachlorohydrate including 0.9:1 including 10.0:1 A number of the aluminum zirconium polychlorohydrate complexes that are useful in the present invention are available commercially.Reheis Chemical Company promotes a series of materials under the general trademark REZALTM. The following Table describes a number of these products together with their specifications: TABLE I 1 REZAL 36G Aluminum zirconium tetrachlorohydrex Gly 2 REZAL 36 Aluminum zirconium trichlorohydrate 3 REZAL 67 Aluminum zirconium pentachlorohydrate 4 REZAL 67 Aluminum zirconium pentachlorohydrate 1 2 3 4 Approx.

Al/Zr ratio 3.6:1 3.6:1 6.7:1 6.7:1 Approx.

metal/Cl ratio 1.4:1 1.6:1 1.7:1 1.7:1 Concentration of solids 35% 100% 40% 100% Aluminum (Al) 5.0%5.7% 16,3%-17.7% 7.6%8.4% 1 9.0%-2 1.0% Zirconium (Zr) 4.4%5.7% 138%-15.2% 3.7% 4.3% 9.2%-1 0.8% Glycine 3.6%-4.7% Chloride (Cl) 5.9%-6.7% 16.0%-19.0% 6.5%-7.2% 16.2%-18.0% Iron (Fe) NMT 50 ppm NMT 100 ppm NMT 50 ppm NMT 100 ppm Heavy metals (as Pb) NMT 10 ppm NMT 20 ppm NMT 10 ppm NMT 20 ppm Particle size (thru 325 mesh) - > 97% min. - > 97% min.

Similar products are marketed by Wickhen Products, Inc. and the Comet Chemical Corporation.

Other suitable actives for use in the present invention comprise mixtures of aluminum chloride with other aluminum salts less acidic than aluminum chloride e.g. aluminum hydroxychloride (or aluminum chlorhydroxide). These are described in Canadian Patent 958,338 issued November 26, 1974.

As will be noted, this patent discloses an aluminum antiperspirant material comprising a mixture of aluminum chloride powder and a powdered water-soluble salt of aluminum which is less acidic than aluminum chloride. The quantities of aluminum chloride and said water-soluble aluminum salt which may comprise the aluminum antiperspirant material may vary somewhat. However, in terms of percentages by weight of the total of powdered aluminum antiperspirant material, the aluminum chloride will generally constitute 10 to 50% and preferably 1 5 to 20%, the balance being made up by said less acidic aluminum salt. In the case of aluminum chlorhydroxide, it is convenient to express the relative amounts of aluminum chloride and aluminum chlorhydroxide in terms of the molar ratios of aluminum to chloride in the dry mixture.In this case, the molar ratio of aluminum to chloride will be in the range of from about 0.78:1 to 1.95:1. Preferably, this ratio will be in the range of from 1.33:1 to 1.79:1.

In preparing this antiperspirant powder mix in addition to the aluminum chloride, any of the other water-soluble aluminum compounds (less acidic than aluminum chloride) known in the prior art as effective as antiperspirant materials may be employed. By way of illustration of these, mention may be made of aluminum chlorhydroxide, aluminum sulfate, "rehydrol" (aluminum chlorhydroxide-propylene glycol complex), complex of zinc phenolsulfonate and chlorhydrol (ratio of aluminum to zinc from 12:1 to 6:1), aluminum potassium sulfate, "Wickenol 363D" (aluminum chlorhydroxide-polyethylene glycol mixture), etc. However, the preferred aluminum compound of this character is aluminum chlorohydrate. In the preferred form, it is employed as an ultrafine powder.

Still another antiperspirant material that can be used herein is prepared from aqueous solutions of aluminum chloride, ACH, aluminum zirconium polychlorohydrate complex and buffering agent e.g.

glycine. These may be spray dried into an impalpable powder and incorporated into stick compositions of this invention.

The quantity of antiperspirant material that will be contained in the sticks of the present invention may vary somewhat. Ordinarily, it will constitute between from about 10.0% to about 60.0% by weight based on the total weight of the composition and preferably from about 15.0% to about 26.0% on the same weight basis.

It is sometimes advantageous to incorporate a lipophillic agent in the antiperspirant sticks of this invention as an optional agent. One class of materials that is of special interest is the propoxylated lower alkyl alcohol ethers. A variety of lipophillic agents may be employed for the present purposes.

One such material that is commercially available is sold under the trade name FLUID AP. The CTFA nomenclature for this material is PPG-1 4 butyl ether.

The quantity of lipophillic agent, when employed, that may be used will be in the range of from 3% to 1 5% by weight based on the total weight of the stick composition. In the preferred cases, this will be from about 5% to about 10% on the same weight basis.

The antiperspirant stick compositions of the present invention may be prepared using the conventional procedures well known to those skilled in this art. A typical procedure is to be found in the U.S. Patent to Geria et al 4,147,750.

The following Examples are given to further illustrate this invention. It is understood, however, that the invention is not limited thereto.

Example 1 Ingredients % W/W Rezal 410 (Al/Zrtrichlorhydrex-gly powder 410) 26.00 Stearyl alcohol 9.00 Castor wax (MP 80) 4.00 FT 300 Wax 2.00 Fluid AP* 3.00 lonol CP** 0.05 Dimethyl isosorbide 47.95 Talc 7.00 Perfume 1.00 100.00 * PPG-1 4 butyl ether (CTFA nomenclature) ** 2,6-di-t-butyl-p-cresol Procedure: 1. Weigh the emollients dimethyl isosorbide and Fluid AP into a suitable stainless steel jacketed kettle and add aluminum zirconium trichlorohydrex-gly powder 410 using moderate lightning mixer agitation.

2. Slowly raise the temperature of this mixture to 11 00F under moderate agitation.

3. In another stainless steel steam jacketed kettle, combine the FT 300 wax, stearyl alcohol, butylated hydroxy toluene, castor wax, talc. Melt until clear by heating to 21 00F.

4. Add the contents of step 2 at 11 00F to step 3 at 1 850F under moderate agitation. A uniform homogeneous suspension results. Cool the batch to 1 250F.

5. Add the perfume at 1250just before filling into containers.

6. Product filling instructions: a. filling temperature 1 58-1 600F b. cooling temperature 1 5 minutes at 400F To test the relative potential for fabric staining of an antiperspirant stick composition of the present invention as compared with a comparable stick composition containing a volatile silicone instead of the dimethyl isosorbide, the following compositions were prepared: Code B FN 1775-85 Ingredient % by Wt.

Stearyl alcohol 9.00 Castor wax MP 80 4.00 FT 300 Wax 2.00 Fluid AP 3.00 lonol CP 0.05 Silicone 71 58* 47.45 Talc 7.00 REZAL 410 26.00 Perfume 4201 AP 1OFF** 1.00 100.00 * Cyclomethicone ** Type: Floral aldehyde Code C FN 1775-84 Commercial antiperspirant stick product having approximately the following composition: Ingredient % by Wt.

Al/Zr tetrachlorohydrex 22-25 Cyclomethicone 45-50 Fluid AP 5-10 Stearyl alcohol 9-1 5 PEG (100) Stearate 1-2 Talc small quantity Perfume small quantity The formula of Example 1 above (FN 1 775-83) was given the code designation A.

Each of the aforesaid formulas were used to treat acrylic, acetate, cotton, nylon, polyester, rayon and wool fabrics. The treated fabrics were then subjected to strength loss test and to a staining test.

Some of the fabrics treated with each of the above formulas showed a loss in tensile strength of more than 10% after one treatment. However, the Code A product of this invention was more effectively removed from all fabric samples treated than was the case with fabrics treated with the Code B or Code C formulas.

The protocol for the staining tests is as follows: Staining Tests: Seven woven fabrics (acrylic, acetate, cotton, nylon, polyester, rayon and wool) are used but are cut 8 by 10 inches in size. The product being tested is applied to each fabric, the fabric is hung on a line and allowed to dry at room temperature for a minimum of 1 6 hours or a maximum of 24 hours. The specimens are washed in a Kenmore home washer. For the cotton fabric we use the normal setting in hot water with a 4 pound load. For the synthetic materials and the wools we use the delicate setting and warm water with a 4 pound load. AATCC detergent is added. Our water is softened to zero hardness.

The samples are hand ironed using appropriate settings for the fabrics involved.

For dry cleaning, a duplicate set of fabrics is stained and after drying for 24 hours they are dry cleaned.

Fabrics are rated for staining by placing them over a black surface and comparing them to a set of Deering Milliken oil stains. The specimens are rated as 5 if no stain is present to a 1 if heavily stained.

Quite often the stains will be yellow or there will be a residue other than the oil. This is noted.

The stain test is repeated four additionai times for a total of five to determine if there is a buildup.

Performance Standards: There shall be no visible stains on white fabrics after laundering and treating 5 times.

The results of these studies were reported as follows: The product stains from all three samples were removed more completely when the fabric swatches were dry cleaned rather than laundered. Product Code A was more effectively removed from the fabric samples than the other two samples. Acetate, which was damaged by sample A, is not a popular everyday fashion fabric. Cotton, which is a popular fabric, especially for underclothes, was stained by deodorant sample C. A rating of 5, no visible stain is needed to pass the standard. Each of the three deodorant samples met this requirement for dry cleaning but not for laundering.

Although the invention has been described with reference to specific forms thereof, it will be understood that many changes and modifications may be made without departing from the spirit of this invention.

Claims (16)

1. An antiperspirant stick composition comprising a waxy material having suspended therein an antiperspirant amount of an active antiperspirant material in particulate form, said stick composition having incorporated therein a water-soluble emollient in sufficient quantity to avoid a waxy feel during the use of said stick and to minimize the drag characteristics of said stick.

2. An antiperspirant stick composition according to Claim 1 in which said water-soluble emollient is present in the range of from about 1 5% to about 80% by weight based on the total weight of the stick composition.

3. An antiperspirant stick composition according to Claim 1 in which said water-soluble emollient is present in an amount of from about 20% to about 60% by weight based on the total weight of the stick composition.

4. An antiperspirant stick composition according to Claims 1,2, or 3 in which said water-soluble emollient is dimethyl isosorbide.

5. An antiperspirant stick composition according to Claim 4 wherein said dimethyl isosorbide is present in the range of from about 35% to about 60% by weight based on the total weight of the composition.

6. An antiperspirant stick composition according to Claim 4 wherein said dimethyl isosorbide is present in an amount in the range of from about 40% to about 50% by weight based on the total weight of the stick composition.

7. An antiperspirant stick composition according to any one of Claims 1 to 6 wherein said waxy material is a low melting point waxy material.

8. An antiperspirant stick composition according to Claim 7 in which said low melting point waxy material has a melting point in the range of from about 1 000F to about 1 500F.

9. A composition according to any one of Claims 1 to 8 in which antiperspirant composition also contains a quantity of a water-insoluble high melting wax.

10. A composition according to Claim 9 in which that water-insoluble high melting wax has a melting point in the range of from about 1 500F to about 21 50F.

11. A composition according to any one of Claims 1 to 10 in which said antiperspirant composition also contains a waxy gelling agent in sufficient amount as to minimize the settling of said particulate antiperspirant material.

12. A composition according to Claim 11 in which said waxy gelling agent is selected from the group consisting of FT-300 Wax, Paraffin Wax 1 33 0--1350F, 1 95 White Wax, Victory White Wax, Multiwax 1 80-M and mixtures thereof.

1 3. An antiperspirant stick composition according to any one of Claims 1 to 12 in which the antiperspirant material is a complex of an aluminum compound, a zirconium compound and an amino acid.

14. An antiperspirant stick composition according to Claim 13 in which said antiperspirant material is Al/Zr trichlorhydrex-gly.

15. An antiperspirant stick composition substantially as hereinbefore described.

16. An antiperspirant stick composition substantially as hereinbefore described with reference to Example 1A.