GB2113116A - Suspension comprising oily and polar liquids - Google Patents

Abstract

A liquid product system containing an oily liquid suspending component and fine particles of a polar liquid component, immiscible in the oily liquid, suspended in said oily liquid component by means of a hydrophobic oxide. The polar liquid may contain an active ingredient dissolved or suspended therein such that the suspension is employable as a body lotion, hair-care or-colouring product, pharmaceutical composition or food dressing. The hydrophobic oxide is typically silica, but may be an oxide of Al, Ti, Zr or Fe.

Description

SPECIFICATION Suspension comprising oily and polar liquids This invention relates to microencapsulated polar liquid products distributed in an oily liquid suspending medium and the processes for preparing the same. More particularly, it concerns product systems containing an oily liquid suspending component having suspended therein fine particles of a polar liquid which is immiscible in said oily liquid suspending component; said fine polar liquid particles being held in suspension in the suspending component by virtue of the presence of ultrafine particles of hydrophobic metal or metalloid oxide (hereinafter referred to collectively as hydrophobic oxide) in said product. In one aspect of the present invention, the particle size of the suspended polar liquid materials may be fine enough to permit the transmission of light through the product.In these instances, the particle sizes of said polar liquids are in the micron size range.

Efforts have been made in the past to provide liquid products in which an aqueous phase has been suspended or distributed in a continuous oil phase. These have taken the form of water-in-oil emulsions in which organic emulsifying agents are employed to emulsify the aqueous phase in the oil.

Such systems, however, have several disadvantages. In the first place, the organic emlusifying agents employed often have negative effects on the function or organoleptic properties of the composition in which they are employed. Thus, for example, when employed in antiperspirant compositions, the emulsifying agents leave a residue on the skin after the composition is applied which interferes with the efficacy of the product. Similarly, in some food preparations the presence of organic emulsifying agents deleteriously affect the taste of the product. Moreover, water-in-oil emulsions employing organic surfactants are prone to be unreliable and show significant variations from batch to batch. This manifests itself often in the "oiling out" of the oil phase in the water-in-oil emulsion products that use these organic surfactants and the loss of integrity of the aqueous phase.

By employing the hydrophobic oxides in accordance with the present invention, the disadvantages noted above are avoided. The hydrophobic oxides are innocuous materials which will not interfere with the activity of the products in which they are contained nor will they impart negative organoleptic affects to such products. Moreover, the suspension products obtained in accordance with the present invention are very stable.

The liquid composition of the present invention contains an oily liquid suspending component having suspended therein fine particles of a polar liquid which is immiscible in said suspending component; said fine particles being held in suspension in said suspending component by virtue of the presence therein of an effective amount of fine particles of a hydrophobic metal oxide such as silica, or a hydrophobic metalloid oxide, wherein said polar liquid advantageously comprises from about 5% to about 80% by weight of said composition; said oily liquid suspending component advantageously comprises from about 20% to about 95% by weight of said composition and said hydrophobic metal or metalloid oxide advantageously comprises from about 0.25% to about 5.0% by weight of said composition.

Figure 1 is a microphotograph of a sample of a composition embodied in the present invention magnified 10 times employing a hydrophobic silica.

Figure 2 is a microphotograph of a composition that employs a conventional pyrogenic silica maynified 10 times and is presented for purposes of comparison with the composition shown in Fig. 1.

The polar liquid component that is contained in the systems of the present invention may be any of a wide variety of materials. These include simple liquids, liquid/liquid solutions, liquid/liquid suspensions, solid/liquid solutions, solid/liquid suspensions. For the most part, the polar liquid component of this invention will take the form of a polar solvent system having dissolved or suspended therein one or more active ingredients which may be liquids or solids.

For the health care field, active ingredients that are useful herein include physiological or pharmaceutical actives such as antiperspirants, deodorants, anesthetics, analgesics, antacids, antihistamines, decongestants, antitussives, laxatives, sunscreening agents, aromatics, antibacterials, antifungals, sialagogue (salivation inducer), etc. These may be employed in preparing antiperspirant products, deodorant products, dentifrices and other oral hygiene products, mouth fresheners, sore throat sprays, topical anesthetic products, liquid antacid products, nasal sprays, cough remedies, cold remedies, etc.

The present invention also has application to cosmetic and toiletry products such as hand and body lotions, hair care products, hair coloring products, cosmetics, etc. In these cases, the active ingredients contained in the polar liquid component may be such things as conditioners, gums, colors, dyes, surfactants, resins, proteins, emollients, glycols, pantanol, vitamins, urea, etc.

The invention may be applied to the food industry in the preparation of such items as salad dressings, toppings, puddings, desserts, etc. In these cases, the active ingredients may be flavor imparting agents such as vinegar, herbs, sugar, syrup, etc.

Any of a variety of polar solvent systems may be used in preparing the polar liquid component of the present invention. These may be simple one component systems or multiple component systems.

To illustrate such solvent systems, mention may be made of such materials as water; alcohol/water; propylene glycol; glycerine; 1,3-butyíene glycol; water/propylene glycol; water/glycerine; water/1 ,3- butylene glycol; sorbitol; water/sorbitol, etc.

The concentration of the actives contained in said polar liquid components will of course vary from application to application and in accordance with the results desired. However, they will be contained at levels to carry out the intended function of the composition. Generally, these concentration levels will be in the range of from about 0.1% to about 40.0% by weight based on the total weight of the composition.

One application of the present invention that is of special interest is in the use of this system in antiperspirant products. In this instance, the solvent system will generally be water or aqueous alcohol in which the active antiperspirant material or materials are dissolved. Such systems will contain the antiperspirant material at levels which are effective for antiperspirant uses. This will ordinarily be in the range of from about 0. 1% to about 40.0% by weight based on the total weight of the composition.

The antiperspirant material utilized in this invention may be any active water-soluble ionizing antiperspirant material capable of yielding antiperspirant active ion species. Many materials of this character are known in this art. It is preferred, however, that the active ionic species contain aluminum, zirconium, tertiary amine salt or a quaternized nitrogen. By way of illustration, the following materials may be mentioned: aluminum chloride, aluminum chlorhydroxide, aluminum formate, aluminum phenol sulfonate, aluminum phosphate, aluminum sulfate, aluminum methionate, zirconyl hydroxy chloride, zirconium lactate, zirconium carbonate, scopolamine hydrobromide, poldine meta sulfate, hexa pyrronium bromide, zirconium oxychloride, aluminum/zirconium tetrachlorohydrate and its glycine complex; aluminum/zirconium trichlorohydrate and its glycine complex, etc. and mixtures thereof.

Another essential component of the systems of the present invention is the suspending component. This is the phase in which the polar liquid component described above is suspended. As previously noted, the suspending component is selected so that the liquid polar component is immiscible and/or insoluble in it. This will generally be an oily hydrophobic liquid at ambient temperatures and will usually be selected with the end use in view. If the product is intended for use as a food item, the oil will usually be an edible oil such as a vegetable oil. These may be exemplified by the following: soybean oil, peanut oil, corn oil, safflower oil, olive oil, etc. and mixtures thereof.

If the product is to be employed as a cosmetic or toiletry, including antiperspirants, the oily material may be a long chain fatty acid ester, a silicone oil, a mineral oil etc. Examples of oily materials that have application in this aspect of the invention include such materials as isopropyl myristate, butyl stearate, dimethyl silicone, apricot oil, diisopropyl sebacate, volatile silicones (e.g. cyclomethicone), etc. and mixtures thereof.

When the'product is to be used for oral hygiene purposes as, for example, as a liquid dentifrice, mouthwash, breath freshener, the oily component might be dimethyl silicone oil, mineral oil, vegetable oil, cyclomethicone, etc. and mixtures thereof.

The present invention may be employed in products useful for medicated products intended to be applied to the mucous membranes e.g. nose, throat, mouth, vagina, anus, etc. These may take the form of medicated sprays (e.g. sore throat sprays, nasal sprays) or products intended to be applied as a gargle or by means of a swab, vaginal or anal dispenser applicators. In these cases, the oily component will usually be one or more of the following: dimethyl silicone oil, mineral oil, vegetable oil, fatty acid esters, etc. and mixtures thereof.

The present invention may also be employed to apply medication to external skin surfaces.

Examples of these would be topical anesthetics, topical analgesics, sunburn preparations, sun blocking or sun tanning compositions, topical antibacterial or antifungal preparations. Oily materials that may be used in these instances as the oily component include such materials as fatty acid esters, mineral oils, silicone oils, etc. and mixtures thereof.

Similarly, the system disclosed herein may be employed in connection with medicated products intended for internal use. These include such products as antacids, laxatives, etc.

The oily component in these instances will be pharmaceutically acceptable materials. By way of example of such oily components, we might mention mineral oil, vegetable oils such as corn oil, soybean oil, peanut oil, etc. and mixtures thereof.

The oily component may comprise only the oily component per se or it may also have incorporated therein other conventional adjuvants. The adjuvants added will be determined by the particular function that the composition is to perform.

The third essential component of the systems of the present invention is the hydrophobic oxide i.e. a pyrogenic oxide having a strongly hydrophobic surface. Hydrophobic pyrogenic silicas are the matrials of choice. These silicas are distinguished from the generally conventional pyrogenic silica (e.g.

Cab-O-Sil) by its mode of preparation which gives it its hydrophobic character. These hydrophobic products are prepared by reacting the conventional pyrogenic silica with an organosilane such as halo alkyl silanes (e.g. dimethyl dichlorosilane) under conditions which cause a chemical reaction to occur with a substantial portion of the hydroxyl groups on the surface of the pyrogenic silica. This gives a new surface structure on the outer or exposed portions of the silica which is largely composed of hydrocarbon groups.

The preparation of hydrophobic silicas that are useful for the purposes of the present invention are described in U.S. Patent 3,393,155 col. 2, line 25 to col. 3, line 18 and in the Example, col. 3, line 70 to col 4, line 6 which is incorporated herein by way of reference. As pointed out therein, the pyrogenic silicas that may be employed in preparing the hydrophobic silicas that can be used herein are those having a surface area of at least about 100 sq. meters per gram and mean equivalent particle diameters of less than 50 millimicrons per gram. In order to provide a sufficiently hydrophobic surface on said silicas for the purpose of this invention, it is merely necessary to attach thereto in suitable concentration chemical complexes bearing hydrocarbon or similar organo groups.The molar concentration of such complexes required per unit of surface area will depend somewhat on the number and size of the organo groups therein. However, for the organo silane complexes of primary interest, which carry from 1 to 3 organo groups mostly of smaller size (e.g. usually not over 7 carbon atoms per group), the concentrations of the attached chemical complexes should be in the range of about 0.2 millimoles or more per 100 sq. meters of surface area of the silica. For the preferred silicas having BET surface areas of at least about 1 50 sq. meters per gram, the carbon content after surface treatment to provide a suitable hydrophobic character will usually be about 1% by weight or more.

A number of hydrophobic silicas sold commercially are employable in the present invention.

These include "Aerosil R 972" or "Silica R972" (Degussa Inc.), "Tullanox 500" (Tulco Inc.), "Silanox" (Cabot Corp.), etc. A material of choice is Silica R 972 currently marketed by Degussa Inc.

Although the hydrophobic silicas described above are by far the materials of choice for use in the present invention, other finely divided metal or metalloid oxides whose surfaces have been rendered hydrophobic in a manner equivalent to that described above in preparation of the hydrophobic silicas may also be employed in this invention. These, in general, will have similar physical characteristics (e.g.

surface area, particle size, concentration of chemical complex and sizes of organo groups) as said hydrophobic silicas. Typical of such metal or metalloid oxides that may be used for these purposes include such materials as aluminas, titanians, zirconium oxides and iron oxides appropriately treated to render them hydrophobic. Materials of this character have been described in published South African patent application 80/1954 open for public inspection October 13, 1 980.

The relative quantities of polar liquid component, liquid oily hydrophobic component and hydrophobic oxide that will be contained in the present compositions may vary widely depending on the intended use of the product and characteristic desired. in general, the various components will be present in relative quantities indicated below: % By wt based on total Component wt. of the composition General Preferred Polar liquid 5.0% to 80.0% 30.0% to 60.0% Oily liquid 20.0% to 95.0% 30.0% to 65.0% Hydrophobic oxide 0.25% to 5.0% 0.5% to 2.0% The compositions of the present invention are prepared generally as follows: the hydrophobic oxide is suspended in the oily liquid phase with high speed stirring. The active ingredients are dissolved in the polar liquid phase.The polar liquid phase is then slowly added to the hydrophobic/oily liquid phase with high speed mixing.

Although Applicant does not want to be bound by any theory, he believes that the hydrophobic oxides function in the present invention by encapsulating the fine particles of polar liquid with a layer of hydrophobic oxide. This is brought about by the special charge characteristics of the hydrophobic oxide. By encapsulating the polar liquid particles with hydrophobic oxide in this fashion, the liquid particles are maintained separated as discrete particles from the continuous oily component that serves as the suspending phase. The liquid particles are thus distributed throughout the oily component in a relatively stable fashion without the need for a surface active agent.

There are several types of evidence that tend to support Applicant's theory of operation of the present invention. One line of evidence are conductivity measurements in which the electrical conductivity of compositions prepared with the hydrophobic silicas in accordance with the present invention is compared with comparable compositions that employ a conventional hydrophilic silica e.g.

Cab-O-Sil M-5. In this study, two compositions were prepared as described below.

Composition A Hydrophobic antiperspirant Ingredients % by wt.

1. Aluminum chlorhydrol (50% aq. sol.) 50.00 2. Water, deionized 10.00 3. Aerosil R 972 (Degussa Inc.) 1.00 4. Silicone P 251 (SWS Corp.) 39.00 100.00 Manufacture 1. Weigh 1 and 2, mix until uniform; 2. Weigh 3 and 4, mix thoroughly; 3. Add step 1 and 2 with high speed shear mixing.

Composition B Hydrophilic antiperspirant Ingredients %bywt.

1. Aluminum chlorhydrol (50% aq. sol.) 50.00 2. Water, deionized 10.00 3. Cab-O-Sil M-5 (Cabot Co.) 1.00 4. Silicon P 251 (SWS Corp.) 39.00 100.00 Manufacture 1. Weigh 1 and 2, mix until uniform; 2. Weigh in separate beaker 3 and 4, mix until uniform 3. Add step 1 and 2 with high speed shear mixing.

Conductivity measurements of Composition A, representative of the present invention, show that this composition does not conduct an electric current. In contrast, the same measurements with Composition B that contains the ordinary pyrogenic silica i.e. Cab-O-Sil M-5 did in fact show that this composition conducts an electric current. This demonstrates that there is a very fundamental difference between these compositions. Moreover, it tends to show that the aqueous phase in Composition A is isolated and separated from the continuous phase and as a consequence, the aqueous phase is not available to serve as a means for conducting an electric current. By contrast in Composition B, the aqueous phase is unprotected with the result that this composition will conduct an electric current.

Another line of evidence which serves to distinguish compositions that employ a hydrophobic silica (Composition A above) from those that employ conventional pyrogenic silica (Composition B) is the microscopic examination of the respective products. In this connection, attention is directed to the drawings which are microphotographs of samples of the respective products. It will be seen that in the composition with the hydrophobic silica (Composition A above), the oil phase is seen as the continuous phase (i.e. background) and the product has a well defined structure. In the case wherein the hydrophilic silica is employed (Composition B above) water is the continuous phase and the structure is very much less defined.

Films of each of the compositions (Composition A and B) were prepared on microscopic slides and the contact angle of water on these films was measured. The hydrophobic silica product (Composition A) gave a very high contact angie, 1050, whereas the hydrophilic silica product (Composition B) gave a low angle, 100, showing wetting.

At a macroscopic level, these differences are manifest in the stability of the respective products.

Samples of Compositions A and B were shaken with about 1 0-20 shakes and then allowed to sit. In about 1/2 hour, the hydrophilic composition (Composition B) separated into three visible phases. After the same 1/2 hour of sitting, the hydrophobic composition (Composition A) showed no separation that could be visibly detected.

The compositions of the present invention may be used and dispensed as such or may be dispensed from an aerosol container. In this event, the present composition would be charged into the aerosol container as the concentrate to which the propellant will be added. In general, such products will contain between about 35.0% to about 70.0% by weight based on the total weight of the composition of this invention as concentrate and between about 25.0% to about 75.0% by weight of propellant.

As noted above, among the preferred compositions of the present invention are antiperspirant products. These compositions will generally contain as the polar liquid from about 25% to about 40% by weight of water based on the total weight of the composition in which is dissolved from about 1 5% to about 25% by weight of active antiperspirant on the same weight basis. The preferred oily liquid is a silicone oil and preferably, a volatile silicone oil. This will ordinarily comprise between about 30% to about 50% by weight based on the total weight of the composition. This sytem required only a small amount of a hydrophobic oxide, preferably a hydrophobic silica, to adequately encapsulate the fine particles of antiperspirant liquid. This will usually be in the range of from about 0.25% to about 2.0% by weight based on the total weight of the composition with the preferred range lying within about 0.5% to about 1.0% on the same weight basis. The beneficial attributes of the antiperspirant composition of this invention are listed below: 1. Highly effective 2. Odorless 3. Greaseless 4. Stainless 5. Fast drying (lack of feel) 6. Non-tacky 7. Lower cost than anhydrous systems 8. Works with all A.P. systems (ACH, Allir, AICI3. 6H2O) 9. Dries to a powder (non-whitening under arms) 10. Can be used as a roll-on; sprayed from a pump spray; squeeze bottle or aerosol system 11.Non-corrosive to metal cans The antiperspirant compositions are generally prepared by the following procedure: the hydrophobic oxide is dispersed in the oil phase with high speed mixing. The antiperspirant actives are dissolved in the polar liquid phase. The polar phase is slowly added to the oily liquid/hydrophobic oxide phase with high speed mixing.

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

The following are the chemical designations of various terms employed in the Examples and other places throughout the specification: 1. REZAL 36G (35% Al/Zr/Gly): Aluminum zirconium tetrachlorohydrex glycine complex.

2. Silicone 251 (SWS): D4:D5 polydimethyl cyclosiloxanes.

3. Silica R-972 (Degussa): Surface coated silicon dioxide manufactured by flame hydrolysis.

4. E.O. 308 (Wicken): Aluminum sesquichlorohydrate.

5. Propellant A-3 1: Isobutane.

Example 1 Roll-on antiperspirant Ingredients % by wt.

Aluminum chlorohydrate (50% aq. sol.) 18.0 AICI3. 6HzO (50% aq. sol.) 6.0 REZAL 36G (36% Al/Zr/Gly) 35.0 Silicone 251 (SWS) 40.0 Silica R-972 (Degussa) 1.0 100.0 The aluminum chlorohydate solution, AICI3. 6H2O solution and the REZAL 36G solution are mixed together. The Silica R 972 is dispersed in the Silicone 251 with high speed mixing. The active salt solution is then slowly added to the silicone/silica dispersion with high speed mixing.

The resultant suspension is packaged in a roll-on container.

Example 2 Pump spray and squeeze bottle antiperspirant Ingredients %bywt.

E.O. 308 (Wicken) 25.0 H20 33.5 Glycine 0.5 Silicone 251 (SWS) 40.0 Silica R-972 (Degussa) 1.0 100.0 The E.O. 308 powder is dissolved in the H2O along with the glycine. The Silica R-972 is dispersed in the Silicone 251 with high speed mixing. The aqueous solution is added to the silicone/silica dispersion with high speed stirring. The resultant suspension is then ready for packaging in either a squeeze spray container or a pump spray container.

Example 3 Aerosol system antiperspirant Ingredients % by wt.

Formulation of Example 2 65.0 Propellant A-31 35.0 100.0 65% of formulation Example 2 is placed in a steel aerosol can. An aerosol valve is crimped on.

35% propellant A-31 is filled through the valve. The contents are shaken and an actuator is placed on the valve and the can sprayed.

Example 4 Aerosol antiperspirant Ingredients %bywt.

Aluminum chlorohydrate (50% aq. sol.) 30.26 Aluminum chloride (50% aq. sol.) 6.72 Glycine 2.02 Silica R-972 0.98 Silicone 251 25.02 Propellant A-31 35.00 100.00 The aluminum chlorohydrate solution, aluminum chloride solution and glycine are mixed together till clear. The Silica R-972 is dispersed in the Silicone 251 with high speed mixing. The aqueous phase is slowly added to the silicone/silica dispersion. The resultant suspension is ready for filling into an aerosol can with the required amount of propellant and an aerosol valve and actuator.

Example 5 Aerosol antiperspirant Ingredients % by wt.

AICI3. 6H2O (50% aq. sol.) 29.44 Magnesium hydroxide 3.68 H20 5.88 Glycine 0.30 Silica R-972 0.90 Silicone 251 19.80 Propellant A-3 1 40.00 100.00 The aluminum chloride solution, magnesium hydroxide, glycine and water are heated to 800C and stirred till clear. The Silica R-972 is dispersed in the Silicone 251 with high speed mixing. The cooled aqueous phase is slowly added to the silicone/silica dispersion with high speed mixing. The resultant suspension is added to an aerosol can, propellant added along with the appropriate valve and actuator.

Example 6 Encapsulated breath freshener Ingredients %bywt.

1. Insoluble saccharin 0.10 2. Water, deionized 49.60 3. Aerosil R-972 (Degussa) 1.00 4. Flavor, peppermint oil 0.30 5. Silicone P-251 49.00 100.00 Manufacture 1. Weigh 1 and 2, mix until soluble; 2. Weigh 3, 4 and 5, mix until uniform; 3. Add step 1 to step 2 with high speed agitation, mix 1 5 minutes, pour into bottle.

Example 7 Encapsulated laxative Ingredients % by wt.

1. Casanthronol (SB Penick) 0.50 2. Water, deionized 49.50 3. Aerosil R-972 (Degussa) 1.00 4. Mineral oil 55/65 (Klearol) 49.00 100.00 Manufacture 1. Weigh 1 and 2, mix until uniform; 2. Weigh 3 and 4, mix until uniform; 3. Add step 1 to step 2 slowly with good agitation, mix 10 minutes, fill into bottle.

Example 8 Encapsulated antacid Ingredients %bywt.

1. Calcium carbonate (Pfizer) 10.00 2. Water, deionized 40.00 3. Aerosil R-972 (Degussa) 1.00 4. Peanut oil (Welch Home Eh Clark) 49.00 100.00 Manufacture 1. Weigh 1 and 2, mix thoroughly; 2. Weigh 3 and 4, mix until uniform; 3. Add step 1 to step 2 with high speed shear mixing, mix 10 minutes, fill into bottle.

Example 9 Encapsulated nasal spray Ingredients %bywt.

1. Oxymetazoline HCI 0.10 2. Water, deionized 49.40 3. Silicone P-251 (SWS Corp.) 50.00 4. Aerosil R-972 (Degussa) 0.50 100.00 Manufacture 1. Weigh 1 and 2, mix until dissolved; 2. Weigh 3 and 4, mix until uniform; 3. Add step 1 to step 2 with high speed shear mixing, mix 10 minutes, fill into bottle.

Example 10 Encapsulated anesthetic lotion Ingredients % by wt.

1. Dyclonine HCI (Ganes) 0.10 2. Water, deionized 39.90 3. Aerosil R-972 (Degussa) 1.00 4. Isopropyl myristate 59.00 100.00 Manufacture 1. Weigh 1 and 2, mix until clear; 2. Weigh 3 and 4, mix until uniform; 3. Add step 1 to step 2 with high speed shear mixing, mix 10 minutes, fill into bottle.

Example 11 Encapsulated hair dressing Ingredients % by wt.

1. DL Panthenol (Hoffman LaRoche) 0.50 2. Water, deionized 49.50 3. Aerosil 9-972 (Degussa) 1.00 4. Mineral oil 55/65 (Klearol) 49.00 100.00 Manufacture 1. Weigh 1 and 2, mix until clear; 2. Weigh 3 and 4, mix until uniform; 3. Add step 1 to step 2 with good high speed mixing, stir 10 minutes, fill into bottle.

Example 12 Encapsulated hair dye Ingredients % by wt.

1. Lawasyn Orange RL 0.05 2. Irgalan Brown SR 0.03 3. Cibal Black BGL 0.02 4. Water, deionized 50.00 5. Aerosil R-972 (Degussa) 1.00 6. Silicon P-251 (SWS Corp.) 48.90 100.00 Manufacture 1. Weigh 1, 2, 3, and 4, mix until uniform; 2. Weigh 5 and 6, mix until uniform; 3. Add step 1 to step 2 with high speed shear mixing, mix 10 minutes, pour into bottle.

Example 13 Encapsulated hand lotion Ingredients %bywt.

1. Water, deionized 30.00 2. Glycerin 29.00 3. Aerosil R-972 (Degussa) 1.00 4. Silicone P-251 (SWS Corp.) 20.00 5. Diisopropyl adipate-Ceraphyl 230 (VanDyk) 20.00 100.00 Manufacture 1. Weigh 1 and 2, mix until uniform; 2. Weigh 3, 4, and 5, mix until uniform; 3. Add step 1 to step 2 slowly with high speed shear mixing, mix 10 minutes, fill into bottle.

Example 14 Encapsulated salad dressing Ingredients % by wt.

1. Cider Vinegar 49.0 2. Aerosil R-972 (Degussa) 1.0 3. Corn oil (Welch Home s Clark) 50.0 100.0 Weigh corn oil and Aerosil mix until uniform. Add vinegar slowly with high speed shear mixing.

Mix 10 minutes, pour into bottle.

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 ambit of this invention.

Claims (7)

Claims

1. A liquid composition containing an oily liquid suspending component having suspended therein fine particles of a polar liquid which is immiscible in said suspending component; said fine particles being held in suspension in said suspending component by virtue of the presence therein of an effective amount of fine particles of a hydrophobic metal oxide such as silica, or a hydrophobic metalloid oxide, wherein said polar liquid advantageously comprises from about 5% to about 80% by weight of said composition; said oily liquid suspending component advantageously comprises from about 20% to about 95% by weight of said composition and said hydrophobic metal or metalloid oxide advantageously comprises from about 0.25% to about 5.0% by weight of said composition.

2. A composition according to claim 1 wherein said polar liquid preferably comprises from about 30% to about 60% by weight of said composition; said oily liquid suspending component preferably comprises from about 30% to about 65% by weight of said composition, and said hydrophobic metal or metalloid oxide preferably comprises from about 0.5% to about 2% by weight of said composition.

3. A composition according to claims 1 or 2 wherein said polar liquid is suitably a polar solvent system, containing from about 0.19/0 to about 40% by weight of an active ingredient such as a physiologically or pharmaceutically active material or a cosmetic and toiletry material or a food preparation, dissolved or suspended therein.

4. A composition according to claim 1, 2 or 3 wherein said active material is at least one of an antiperspirant, deodorant, anaesthetic, analgesic, antacid, antihistamine, decongestant, antitussive, laxative, sunscreening agent, aromatic, antibacterial, antifungal, sialogogue, hand or body lotion, a hair dressing product, a hair coloring or hair dyeing product, an oral hygiene product, and a breath freshener.

5. A process for preparing compositions defined in Claim 1 which comprises suspending said hydrophobic oxide in said oily liquid suspending component with high speed mixing, dissolving or suspending an active ingredient in said polar liquid and then adding said polar liquid containing said active ingredient to said oily liquid suspending component containing said hydrophobic oxide with high speed mixing.

6. A composition as claimed in claim 1 prepared by a process as claimed in claim 5.

7. A composition as claimed in claim 1 prepared by a procedure substantially as described in any of the foregoing Examples 1 to 14.