WO1998011870A1 - Liquid personal cleansing compositions which contain an encapsulated lipophilic skin moisturizing agent comprised of relatively large droplets - Google Patents

Abstract

Liquid personal cleansing compositions which comprise from about 1 % to about 35 % of encapsulated lipophilic skin moisturizing agents, from about 0.1 % to about 5 % of a stabilizer, from about 5 % to about 30 % of a lathering surfactant and water are disclosed. The encapsulated lipophilic skin moisturizing agent comprises a lipophilic skin moisturizing agent encapsulated within a complex coascervate comprising a polycation and a polyanion. The lipophilic skin moisturizing agent comprises droplets having a particle size distribution such that at least about 10 % by weight of the droplets have a diameter of at least about 100 microns. The encapsulated lipophilic skin moisturizing agent is essentially free of cross-linking agent.

Description

LIQUID PERSONAL CLEANSING COMPOSITIONS WHICH CONTAIN AN ENCAPSULATED LIPOPHILIC SKIN MOISTURIZING AGENT COMPRISED OF

RELATIVELY LARGE DROPLETS

TECHNICAL FIELD

The present invention relates to liquid personal cleansing compositions which provide clinically efficacious moistuπzation to the skin The liquid personal cleansing compositions of the present invention are emulsions which contain a moisturizing phase compπsing an encapsulated lipophilic skin moisturizing agent and an aqueous cleansing phase compπsing a surfactant and a stabilizer The lipophilic moisturizing agents which comprise the liquid personal cleansing compositions herein themselves compnse droplets which have a particle size distribution such that at least about 10% by weight of the droplets are greater than about 00 microns in diameter

BACKGROUND OF THE INVENTION

Liquid personal cleansing products are becoming more popular in the United States and around the world Desirable liquid personal cleansuig compositions must meet a number of catena For example, in order to be acceptable to consumers, a liquid personal cleansing product must exhibit good cleaning properties, must exhibit good lathering characteristics, must be mild to the skin (not cause drying or irritation) and preferably should even provide a moistunzation benefit to the skin

Liquid personal cleansing products which contain high levels of lipophilic skin conditioning agents have been disclosed In fact, consumer products, such as Olay Moisturizing Body Wash, which, especially when used with the Olay Cleansing Puff, deposit lipophilic skin conditioning agents on the skin are enormously popular with consumers Nevertheless, some consumers would prefer to have an even greater moistunzing benefit delivered from these liquid personal cleansing products Therefore, it would be desirable to provide a liquid personal cleansing composition with even greater moistunzing properties

It has now been found that the deposition of a lipophilic skin moisturizing agent on the skin can be dramatically increased if the lipophilic skin moistunzing agent comprises relatively large oil droplets Unfortunately, it can be difficult to formulate a personal cleansing composition which contains diis type of lipophilic skin moisturizing agent because the large oil droplets tend to be destroyed (broken down into smaller particles) during the processing, especially the packaging, of the liquid compositions. It has now also been found, however, that the integrity of the relatively large particles comprising the lipophilic skin moisturizing agent can be preserved by encapsulating the moisturizing agent within a complex coascervate. The complex coascervate must be of a nature such that it protects the integrity of the large particles during processing, but still allows the lipophilic skin moisturizing agent contained therein to deposit on the skin.

SUMMARY OF THE INVENTION

The present invention relates to moisturizing liquid personal cleansing emulsion compositions which comprise a moisturizing phase and an aqueous cleansing phase. The moisturizing phase comprises from about 1% to about 35% by weight of the composition of encapsulated lipophilic skin moisturizing agents. The aqueous cleansing phase comprises from about 0.1% to about 10% by weight of the composition of a stabilizer, from about 5% to about 30% by weight of the composition of a lathering surfactant and water.

The encapsulated lipophilic skin moisturizing agent comprises a lipophilic skin moisturizing agent encapsulated within a complex coascervate comprising a polycation having a minimum filtrate weight of 10 grams and a polyanion. The complex coascervate has a hardness ranging from about 50 to about 1400 grams force. The lipophilic skin moisturizing agent comprises droplets having a particle size distribution such that at least about 10% by weight of the droplets have a diameter of at least about 100 microns. DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to liquid personal cleansing compositions which provide clinically efficacious moisturization to the skin. As used herein, "liquid personal cleansing compositions" refers to rinse off personal cleansing products, including, but not limited to, shower washes, liquid hand soaps, and shampoos. T e liquid personal cleansing compositions of the present invention are emulsions which contain a moisturizing phase comprising a lipophilic skin moisturizing agent and an aqueous cleansing phase comprising a surfactant, a stabilizer, and water. The lipophilic moisturizing agents which comprise the liquid personal cleansing compositions herein themselves comprise droplets which have a particle size distribution such that at least about 10% by weight of the droplets have a diameter greater than about 100 microns. For purposes of the present invention, the diameter of a particle refers to the longest length of the particle. It has been found that when at least about 10% by weight of the droplets comprising the lipophilic skin moisturizing agent have a diameter of greater than about 100 microns, that the liquid personal cleansing composition which contains the lipophilic skin moisturizing agent will provide clinically efficacious moisturization to the skin. Unfortunately, it is difficult to prepare personal cleansmg composition products wherem the lipophilic skin moisturizing agents have the desired particle size ώstπbution, even when the droplets initially have the desired size, because the large droplets tend to be destroyed (broken down into smaller droplets) duπng the processmg, especially the packaging, of the cleansmg composition It has now been found, however, that liquid personal cleansmg compositions which contam lipophilic skin moistuπzmg agents which have the desired particle size distribution can be obtained by forming a complex coascervate around the lipophilic skm moistuπzmg agent to protect the integπty of the large droplets duπng processmg (especially packaging) of the liquid personal cleansmg composition However, in order the obtain the moistuπzmg benefit, the lipophilic skm moistuπzmg agent must be able to deposit on the skm Therefore, the complex coascervate encapsulating the lipophilic skm moistuπzmg agent duπng the processmg of the liquid personal cleansmg composition must be of a nature such that it will still allow the lipophilic skm moistuπzmg agent contained within to deposit on the skm

The key factors affecting the ability of the coascervate to protect the integπty of the particles dunng processmg and still allow the moistunzmg agent to deposit on the skm are the relative hardness/softness of the complex coascervate and the thickness of the complex coascervate In particular, the complex coascervate must be hard enough and thick enough to protect the mtegπty of the lipophilic skm moistuπzmg agent particles dunng processmg of the liquid personal cleansmg compositions, but soft enough and thin enough to allow the lipophilic skm moistunzmg agent encapsulated within to deposit on the skin

It has been found that a suitable hardness for the complex coascervate ranges from about 50 to about 1400 grams force, preferably from about 400 to about 1200 grams force, more preferably from about 600 to about 1000 grams force, as measured by the Strength of Coascervate Method hereinafter descnbed in the Analytical Methods Section It has further been found that the complex coascervate is of suitable thickness when at least about 10%, preferably at least about 30%, more preferably at least about 50%, and most preferably at least about 70% of the encapsulated lipophilic skm moistuπzmg agent particles the final product are nonspheπcal in shape, as determined by the % Nonspheπcal Particle Method hereinafter descnbed in the Analytical Methods Section For purposes of the present invention, a particle is nonspheπcal if it has an aspect ratio (length divided by width) of greater than 1 1 It is believed that the nonspheπcal shape of the particles is directly related to the thickness of the complex coascervate and that the thickness of the complex coascervate is directly proportional to deposition at a given particle size distnbution

Liquid personal cleansmg compositions which contam lipophilic skm moistuπzmg agents wherem at least 10% by weight of the droplets have a diameter of greater than about 100 microns, including the materials contained therein and processes for preparing, are described in detail as follows:

I. Ingredients

A. Encapsulated Lipophilic Skin Moisturizing Agent 1. Complex Coascervate

One way to maintain the large droplet size of the droplets comprising the lipophilic skin moisturizing agent during the processing of the liquid personal cleansing compositions and to still enable the deposition of the lipophilic skin moisturizing agent to the skin is to form a complex coascervate around the lipophilic skin moisturizing agent. As hereinbefore described, the complex coascervate must be of a nature such that it protects the integrity of the large particles during the processing of the liquid personal cleansing composition, but still allows the lipophilic skin moisturizing agent contained therein to deposit on the skin. The complex coacervate described herein will have the requisite characteristics to provide the benefits hereinbefore described.

The coascervate is a complex of a polycation having a minimum filtrate weight of 10 grams and a polyanion. The complex coascervate typically comprises from about 0.1% to about 15%, preferably from about 0.5% to about 10%, more preferably from about 1% to about 5% polycation and from about 0.01% to about 10%, preferably from about 0.05% to about 5%, more preferably from about 0.1 % to about 1% polyanion. The ratio of polycation to polyanion in the complex coascervate ranges from about 30: 1 to about 1:5, preferably from about 20: 1 to about 1 :2, more preferably from about 15: 1 to about 1:1. Typically, from about 50% to about 95% of each capsule consists of the lipophilic skin moisturizing agent. The ratio of the lipophilic skin moisturizing agent to the coascervate complex typically ranges from about 5: 1 to about 1:5, preferably from about 3: 1 to about 1:3, more preferably from about 2: 1 to about 1 :2.

Polycations which are suitable for use in the present invention have a minimum filtrate weight of about 10 grams, preferably about 15 grams, more preferably about 20 grams, as measured by the Filtrate Weight Method set forth hereinafter in the Analytical Methods section. Polycations having a filtrate weight of less than about 10 grams will not form a thick enough coascervate , when combined with the polyanion, to protect the integrity of the lipophilic skin moisturizing agent particles during processing of the liquid personal cleansing composition.

Proteins having a average molecular weight ranging from about 50 to about 1,000,000 are preferred polycations for use in the present invention. Preferred proteins for use herein include, for example, gelatin, ovalbumin, serum albumin, casein, chitin, and mixtures thereof.

Gelatin is an especially preferred protein for use as a polycation in the present invention. Gelatins can be characterized according to bloom strength. Bloom strength is the force (measured in grammes) required to depress the surface of a 6 3/3% w/w gel, matured at 10°C for 16-18 hours, a distance of 4mm using a flat-bottomed plunger 12 7 mm in diameter The instrument used is the Bloom Gelometer A semi-automated version, the Bloom Electromc Jelly Tester, can also be used Gelatins having a bloom strength rangmg from about 60 to about 300, preferably from about 100 to about 300, more preferably from about 150 to about 300 and most preferably from about 200 to about 300 are suitable for use here

Other polycations having the requisite filtrate weight, such as polyvmylamine and cellulose denvatives, may also suitably be employed for use herem

The polyanions suitable for use herem mcludes, for example, polyphosphate, gum arable, sodium alginate, caπageenan, cellulose acetate, phthalate, pectin, carboxymethylcellulose, ethylene maleic anhydnde, and mixtures thereof

Polyphosphate is an especially preferred polyanion for use herem 2 The Lipophilic Skin Moistunzing Agent

A lipophilic skin moistuπzmg agent is employed m the personal cleansmg compositions herem The lipid skin moistuπzmg agent provides a moistuπzmg benefit to the user of the personal cleansmg product when the lipophilic skm moistunzmg agent is deposited to the user's skm It has been found that deposition of the lipophilic skm moistuπzmg agent is dramatically increased when at least about 10%, preferably at least about 20%, more preferably at least about 30%, even more preferably at least about 50% and most preferably at least about 80% by wei ht of the droplets compπsing the lipophilic skm moistuπzmg agent have a diameter of greater than about 100 microns, preferably greater than about 200 microns, more preferably greater than about 300 microns, even more preferably greater than about 400 microns, and most preferably greater than about 500 microns, as measured by the Particle Size Distnbution Method hereinafter set forth in the Analytical Methods section In general, the larger the number of large-particle size lipophilic skm moistuπzmg agent particles, and the larger the particle size of the particles, the greater the deposition of the moistunzmg agent on the skm

Two types of rheological parameters are used to define the lipophilic skm moistunzmg agent used herem The viscosity of the lipophilic skm moistuπzmg agent is represented by consistency (k) and shear dex (n) The lipophilic skm moistunzmg agents for use herem typically have a consistency (k) rangmg from about 5 to about 5,000 poise, preferably from about 10 to about 3,000 poise, more preferably from about 50 to about 2,000 poise, as measured by the Consistency (k) Method hereinafter set forth m the Analytical Methods section Suitable lipophilic skm moistunzmg agents for use herem further have a shear mdex (n) rangmg from about 0 01 to about 0 9, preferably from about 0 1 to about 0 5, more preferably from about 0 2 to about 0 5, as measured by the Shear Insex Method heremafter set forth m the Analytical methods section While not being bound by any theory, it is believed that lipophilic skin moisturizing agents having rheology properties other than those defined herein are either too easily emulsified and hence will not deposit, or are too "stiff' to adhere or deposit on to skin and provide a moisturization benefit. In addition, the rheological properties of the lipophilic skin moisturizing agent are also important to user perception. Some lipophilic skin moistunzing agents, on deposition to the skin, are considered too sticky and are not prefeπed by the user.

In some cases, the lipophilic skin moisturizing agent can also desirably be defined in terms of its solubility parameter, as defined by Vaughan in Cosmetics and Toiletries. Vol. 103, p. 47-69, October 1988. A lipophilic skin moisturizing agent having a Vaughan solubility Parameter (VSP) from 5 to 10, preferably from 5.5 to 9 is suitable for use in the liquid personal cleansing compositions herein.

A wide variety of lipid type materials and mixtures of materials are suitable for use as the lipophilic skin moisturizing agents in the personal cleansing compositions of the present invention. Preferably, the lipophilic skin conditioning agent is selected from the group consisting of hydrocarbon oils and waxes, silicones, fatty acid derivatives, cholesterol, cholesterol derivatives, di and tri-glycerides, vegetable oils, vegetable oil derivatives, liquid nondigestible oils such as those described in U.S. Patents 3,600, 186 to Mattson, Issued August 17, 1971 and 4,005,195 and 4,005,196 to Jandacek et al; both issued January 25, 1977, all of which are herein incorporated by reference, or blends of liquid digestible or nondigestible oils with solid polyol polyesters such as those described U.S. Patent 4,797,300 to Jandacek; issued January 10, 1989; U S Patents 5,306,514, 5,306,516 and 5,306,515 to Letton; all issued April 26, 1994, all of which are herein incorporated by reference, and acetoglyceride esters, alkyl esters, alkenyl esters, lanolin and its derivatives, milk -tri-glycerides, wax esters, beeswax derivatives, sterols, phospholipids and mixtures thereof. Fatty acids, fatty acid soaps and water soluble polyols are specifically excluded from our definition of a lipophilic skin moisturizing agent.

Hydrocarbon oils and waxes: Some examples are petrolatum, mineral oil micro- crystalline waxes, polyalkenes (e.g. hydrogenated and nonhydrogenated polybutene and polydecene), paraffins, cerasin, ozokerite, polyethylene and perhydrosqualene Blends of petrolatum and hydrogenated and nonhydrogenated high molecular weight polybutenes wherein the ratio of petrolatum to polybutene ranges from about 90: 10 to about 40:60 are also suitable for use as the lipid skin moisturizing agent in the compositions herein.

Silicone Oils: Some examples are dimethicone copolyol, dimethylpolysiloxane, diethylpolysiloxane, high molecular weight dimethicone, mixed C1-C30 alkyl polysiloxane, phenyl dimethicone, dimethiconol, and mixtures thereof. More prefeπed are non-volatile silicones selected from dimethicone, dimethiconol, mixed C1-C30 alkyl polysiloxane, and mixtures tJiereof. Nonlimiting examples of silicones useful herein are described in U.S. Patent No. 5,011,681, to Ciotti et al., issued April 30, 1991, which is incorporated by reference.

Pi and tri-glvcerides: Some examples are castor oil, soy bean oil, derivatized soybean oils such as maleated soy bean oil, safflower oil, cotton seed oil, corn oil, walnut oil, peanut oil, olive oil, cod liver oil, almond oil, avocado oil, palm oil and sesame oil, vegetable oils and vegetable oil derivatives; coconut oil and derivatized coconut oil, cottonseed oil and derivatized cottonseed oil, jojoba oil, cocoa butter, and the like.

Acetoglyceride esters are used and an example is acetylated monoglycerides.

Lanolin and its derivatives are prefeπed and some examples are lanolin, lanolin oil, lanolin wax, lanolin alcohols, lanolin fatty acids, isopropyl lanolate, acetylated lanolin, acetylated lanolin alcohols, lanolin alcohol linoleate, lanolin alcohol riconoleate.

It is most preferred when at least 75 % of the lipophilic skin conditioning agent is comprised of lipids selected from the group consisting: petrolatum, blends of petrolatum and high molecular weight polybutene, mineral oil, liquid nondigestible oils (e.g. liquid cottonseed sucrose octaesters) or blends of liquid digestible or nondigestible oils with solid polyol polyesters (e.g. sucrose octaesters prepared from C22 fatty acids) wherein the ratio of liquid digestible or nondigestible oil to solid polyol polyester ranges from about 96:4 to about 80:20, hydrogenated or nonhydrogenated polybutene, micro-crystalline wax, polyalkene, paraffin, cerasin, ozokerite, polyethylene, perhydrosqualene; dimethicones, alkyl siloxane, polymethylsiloxane, methylphenylpolysiloxane and mixtures thereof. When as blend of petrolatum and other lipids is used, the ratio of petrolatum to the other selected lipids (hydrogenated or unhydrogenated polybutene or polydecene or mineral oil) is preferably from about 10: 1 to about 1 :2, more preferably from about 5: 1 to about 1 : 1.

3. Preparation

The liquid personal cleansing compositions herein comprise from about 1% to about 35%, preferably from about 5% to about 30%, more preferably from about 10% to about 25% of the encapsulated lipophilic skin moisturizing agent. The amount of encapsulated lipophilic skin moisturizing agent that is included in the personal cleansing compositions of the present invention is an amount such that the composition contains from about 1% to about 30%, preferably from about 3% to about 25%, more preferably from about 5% to about 25% of lipophilic skin moisturizing agent. Typically, the personal cleansing composition will contain from about 0.1% to about 5%, preferably from about 0.3% to about 3% , more preferably from about 0.5% to about 1.5% of the polycation and from about 0.01% to about 1% .preferably from about 0.02% to about 0.5%, more preferably from about 0.03% to about 0.2% of the polyanion. The encapsulated lipophilic skin moisturizing agent herein can be prepared by preparing a hot aqueous solution of a polycation and a polyanion at a temperature greater than the melting point of the lipophilic skin moisturizing agent, and mixing in the lipophilic skin condition agent under low shear conditions, without utilizing a cross linking agent. When the polycation is gelatin, the pH is adjusted to from about 3.5 to about 5.0. The polycation and the polyanion then complex to form a coascervate, and, upon cooling, the coascervate separates as a wall which encapsulates the lipophilic skin moisturizing agent.

It is important that the mixture of polycation, polyanion and lipophilic skin moisturizing agent be essentially free of cross-linking agent in order to ensure that the complex coascervate has the requisite hardness characteristics. When substantial amounts of a cross linking agent are employed herein, the complex coascervate will be too hard to allow the lipophilic skin moisturizing agent contained therein to deposit on the skin. As used herein "essentially free of cross-linking agent" means that the mixture contains less than about 0.25% of cross-linking agent. Cross-linking agents are elements, groups or compounds which bridge together two chains of polymer molecules by joining certain carbon atoms of the chains by primary chemical bonds. Cross-linking agents include for example, gluteraldehyde, urea, formaldehyde, phenol, tannic acid, and mixtures thereof.

The particle size of the lipophilic skin moisturizing agent is a function of the RPM of the mixer, the composition of the aqueous solution and the rheology of the aqueous solution. In general, the lower the RPM of the mixer, the larger the particle size of the lipophilic skin moisturizing agent. Also, to achieve a larger particle size for the lipophilic skin moisturizing agent, the aqueous solution is preferably void of emulsifiers, such as surfactants, and should be essentially of a newtonian and nonviscous rheology.

B. Stabilizer

The liquid personal cleansing compositions of the present invention also typically contain from about 0.1% to about 10%, preferably from about 0.25% to about 8%, more preferably from about 0.5% to about 5% of a stabilizer.

The stabilizer is used to form a crystalline stabilizing network in the emulsion that prevents the lipophilic skin moisturizer agent droplets from coalescing and phase splitting in the product. The network exhibits time dependent recovery of viscosity after shearing (e.g., thixotropy).

The stabilizers used herein are not surfactants. The stabilizers provide improved shelf and stress stability, but allow the oil-in-water emulsion to separate upon lathering, and thereby provide for increased deposition of the lipophilic skin moisturizing agent onto the skin. This is particularly true when the oil-in-water cleansing emulsions of the present invention are used in conjunction with a polymeric diamond meshed sponge implement such as that described in Campagnoli; U.S. Patent 5,144,744; Issued September 8, 1992, herein incorporated by reference.

In one embodiment of the present invention, the stabilizer employed in the personal cleansing compositions herein comprises a crystalline, hydroxyl-containing stabilizer. This stabilizer can be a hydroxyl-containing fatty acid, fatty ester or fatty soap water-insoluble wax-like substance or the like.

The crystalline, hydroxy-containing stabilizer is selected from the group consisting of: (i) CH₂ - ORj

I

CH - OR₂

I

CH ₂- OR₃

wherein

O

Rl is -C-R (CHOH)_cR5(CHOH^R_6;

R₂ is Ri or H

R3is R_j or H

R ^{is c}0-20 Alkyl

^R5 ^{is c}0-20 Alkyl,

■&6 ^{is c}0-20 Alkyl

R₄ + R₅ + R₆= C 10.22 and wherein 1< x+y <4;

(ϋ) O

R7-C-OM

wherein

R₇ is -R4(CHOH)_xR₅(CHOH)yR₆

M is Na⁺, K+ or Mg÷^"1", or H; and

iii) mixtures thereof;

Some preferred hydroxyl-containing stabilizers include 12-hydroxystearic acid, 9,10- dihydroxystearic acid, tri-9,10-dihydroxystearin and tri-12-hydroxystearin (hydrogenated castor oil is mostly tri-12-hydroxystearin). Tri-12-hydroxy stearin is most prefeπed for use in die emulsion compositions herein.

When these crystalline, hydroxyl-containing stabilizers are utilized in the personal cleansing compositions herein, they are typically present at from about 0.5% to 10%, preferably from 0.75% to 8%, more preferably from 1.25% to about 5% of the liquid personal cleansing compositions. The stabilizer is insoluble in water under ambient to near ambient conditions.

Alternatively, the stabilizer employed in the personal cleansing compositions herein can comprise a polymeric thickener. When polymeric thickeners as the stabilizer in the personal cleansing compositions herein, they are typically included in an amount ranging from about 0.01% to about 5%, preferably from about 0.3% to about 3%, by weight of the composition. The polymeric thickener is preferably an anionic, nonionic, cationic or hydrophobically modifier polymer selected from the group consisting of cationic polysaccharides of the cationic guar gum class with molecular weights of 1,000 to 3,000,000, anionic cationic and nonionic homopolymers derived from acrylic and/or methacrylic acid, anionic cationic and nonionic cellulose resins, cationic copolymers of dimethyldialkylammomum chloride and acrylic acid, cationic homopolymers of dimethylalkylammonium chloride, cationic polyalklene and ethoxypolyalkylene imines, polyethylene glycol of molecular weight from 100,000 to 4,000,000, and mixtures thereof Preferably, the polymer is selected from the group consisting of Sodium Polyacrylate, hydroxy ethyl Cellulose, Cetyl Hydroxy Ethyl Cellulose, and Polyquaternium 10.

Alternatively, the stabilizer employed in the personal cleansing compositions herein can comprise C 10-C22 ethylene glycol fatty acid esters. C 10-C22 ethylene glycol fatty acid esters can also desirably be employed in combination with the polymeric thickeners hereinbefore described. The ester is preferably a diester, more preferably a C14-C18 diester, most preferably ethylene glycol distearate. When C10-C22 ethylene glycol fatty acid esters are utilized as the stabilizer in the personal cleansing compositions herein, they are typically present at from about 3% to about 10%, preferably from about 5% to about 8%, more preferably from about 6% to about 8% of the personal cleansing compositions.

Another class of stabilizer which can be employed in the personal cleansing compositions of the present invention comprises dispersed amorphous silica selected from the group consisting of fumed silica and precipitated silica and mixtures thereof. As used herein the term "dispersed amorphous silica" refers to small, finely divided non-crystalline silica having a mean agglomerate particle size of less than about 100 microns.

Fumed silica, which is also known as arced silica, is produced by the vapor phase hydrolysis of silicon tetrachloride in a hydrogen oxygen flame. It is believed that the combustion process creates silicone dioxide molecules which condense to form particles. The particles collide, attach and sinter together. The result of this process is a three dimensional branched chain aggregate. Once the aggregate cools below the fusion point of silica, which is about 1710°C, further collisions result in mechanical entanglement of die chains to form agglomerates, precipitated silicas and silica gels are generally made in aqueous solution. See, Cabot Technical Data Pamphlet TD-100 entitled "CAB-O-SIL® Untreated Fumed Silica Properties and Functions", October 1993, and Cabot Technical Dat Pamphlet TD-104 entitled "CAB-O-SIL® Fumed Silica in Cosmetic and Personal Care Products", March 1992, both of which are herein incorporated by reference.

The fumed silica preferably has a mean agglomerate particle size ranging from about 0.1 microns to about 100 microns, preferably from about 1 micron to about 50 microns, and more preferably from about 10 microns to about 30 microns. The agglomerates are composed of aggregates which have a mean particle size ranging from about 0.01 microns to about 15 microns, preferably from about 0.05 microns to about 10 microns, more preferably from about 0.1 microns to about 5 microns and most preferably from about 0.2 microns to about 0.3 microns. The silica preferably has a surface area greater than 50 sq. m/gram, more preferably greater than about 130 sq. m./gram, most preferably greater than about 180 sq. m./gram.

When amorphous silicas are used as the stabilizer herein, they are typically included in the emulsion compositions at levels ranging from about 0.1% to about 10%, preferably from about 0.25% to about 8%, more preferably from about 0.5% to about 5%.

A fourth class of stabilizer which can be employed in the personal cleansing compositions of the present invention comprises dispersed smectite clay selected from the group consisting of bentonite and hectorite and mixtures thereof. Bentonite is a colloidal aluminum clay sulfate. See Merck Index, Eleventh Edition, 1989, entry 1062, p. 164, which is incorporated by reference. Hectorite is a clay containing sodium, magnesium, lithium, silicon, oxygen, hydrogen and flourine. See Merck Index, eleventh Edition, 1989, entry 4538, p. 729, which is herein incorporated by reference.

When smectite clay is employed as the stabilizer in the personal cleansing compositions of the present invention, it is typically included in amounts ranging from about 0.1% to about 10%, preferably from about 0.25% to about 8%, more preferably from about 0.5% to about 5%. c. THE LATHERING SURFACTANT

The personal cleansing compositions of the present invention also comprises a lathering surfactant selected from the group consisting of anionic surfactants; nonionic surfactants, cationic surfactants, amphoteric surfactants, and mixtures thereof.

The lathering surfactant is defined herein as a surfactant or surfactant mixture thereof that when combined have an equilibrium surface tension of between 15 and 50 dynes/cm, more preferably between 25 and 40 dynes/cm as measured at the CMC (critical micelle concentration) at 25 °C. Some surfactant mixes can have a surface tension lower than those of its individual components.

The personal cleansing compositions herein comprise from about 5% to about 30%, preferably from about 5% to about 25%, and most preferably from about 10% to about 25% of a lathering surfactant.

Anionic surfactants useful herein include: acyl isethionates, acyl sarcosinates, alkylglycerylether sulfonates, alkyl sulfates, alkyl sulfates, acyl lactylate, methylacyl taurates, paraffin sulfonates, linear alkyl benzene sulfonates, N-acyl glutamates, alkyl sulfosuccinates, alpha sulfo fatty acid esters, alkyl ether carboxylates, alkyl phosphate esters, ethoxylated alkyl phosphate esters,, alpha olefin sulphates, the alkyl ether sulfates (with 1 to 12 ethoxy groups) and mixtures thereof, wherein said surfactants contain C8 to C22 alkyl chains and wherein the counterion is selected from the group consisting of: Na, K, NH4, N(CH2CH2OH)3- The anionic surfactant is more prefeπed when selected from the group consisting of acyl isethionate, acyl sarcosinates, acyl lactylates, alkyl sulfosuccinates, alkylglycerylether sulfonates, methylacyl taurates, alkyl ether sulfates, alkyl sulfates, alkyl phosphate esters and mixtures thereof, wherein said surfactants contain has C 8 to C 14 alkyl chains and is present at a level of from about 8% to about 20%.

Amphoteric synthetic surfactants cannot serve as the sole surfactant in this product, but are prefeπed as a co-surfactant at a lower level of from about 1 part to about 10 parts, by weight and the more prefeπed types are selected from alkyl-ampho mono- and di-acetates, alkyl betaines, alkyl dimethyl amine oxides, alkyl sultaines, alkyl amidopropyl betaines, alkyl amidopropyl hydroxysultaines, and mixtures thereof, wherein said surfactants contain C8 to C22 alkyl chains.

Nonionic synthetic surfactant cannot serve as the sole surfactant in this product, but can be used as a co-surfactant at a lower level of from about 1% to about 15% by weight. The more prefeπed types selected from the group consisting: alkyl glucose amides, alkyl glucose esters, polyoxyethylene amides, fatty alkane amides, alkyl amine oxides, alkyl polyglucosides, polyoxy ethylene alkyl phenols, polyoxyethylene esters of fatty acids, EO/PO block co-polymers such as polyoxamines and poloxamers, sorbitan esters and alcohol esters, and mixtures thereof.

Cationic synthetic surfactant cannot serve as the sole surfactant in this product, but are prefeπed as a co-surfactant at a lower level of from about 0.5% to about 6%, by weight. The more prefeπed types of cationic surfactants are selected from the group consisting: alkyl trimonium chloride and methosulfate, and dialkyldimonium chloride and methyl sulphate, and alkyl alkonium chloride and methyl sulphate and mixtures thereof. These surfactants contain C12 to C24 carbon atoms per alkyl chain. The most prefeπed cationic is selected from the group consisting of stearalkonium chloride, stearyltrimonium chloride, Di-stearyl-dimonium chloride, and mixtures thereof. Cationic surfactants may also act as a lipid deposition aid.

The liquid emulsions compositions herein can also optionally contain C8- C14 fatty acid soap; where the soap has a counterion selected from the group consisting of K and N(CH2CH20H)3, and mixtures thereof, in addition to the lathering synthetic surfactant. In one prefeπed embodiment of the present invention, the liquid personal cleansing compositions comprise less than about 5%, preferably less than about 4%, more preferably less than about 3% and most preferably less than about 2% by weight of fatty acid soap.

D. WATEE

The moisturizing personal cleansing compositions of the present invention comprise water as an essential component. The water is typically present at a level of from about 30% to about 80%, preferably from about 40% to about 75%, and most preferably from about 40% to about 65% of the personal cleansing compositions of the present invention.

E. Optional Ingredients

The personal cleansing compositions of the present invention can also contain a number of optional ingredients.

For example, the liquid personal cleansing compositions of the present invention can optionally include water-dispersible, gel-forming polymers. This polymer is preferably a anionic, nonionic, cationic or hydrophobically modified polymer, selected from the group consisting of cationic polysaccharides of the cationic guar gum class with molecular weights of 1,000 to 3,000,000, anionic, cationic and nonionic homopolymers derived from acrylic and/or methacrylic acid, anionic, cationic and nonionic cellulose resins; cationic copolymers of dimethyldialkylammonium chloride and acrylic acid; cationic homopolymers of dimethyldialkylammonium chloride; cationic polyalkylene and ethoxypolyalkylene i ines polyethylene glycol of molecular weight from 100,00 to 4,000,000; and mixtures thereof. Preferably, the polymer is selected form die group consisting of Sodium Polyacrylate, Hydroxy Ethyl Cellulose, Cetyl Hydroxy Ethyl Cellulose, and Polyquaternium 10.

The polymer is preferably included in the compositions of the present invention at a level of from about 0.1% to 1%, more preferably 0.1% to 0.5%. The polymers can improve the sensory feel of the lipid on skin in addition to providing product stabilization. The improved sensory feel results from reduced tackiness and greasiness and improved smoothness. It is an especially prefeπed embodiment to use mixture of polymers, some of which are prefeπed for product stabilization, some are prefeπed for improved sensory feel. Prefeπed polymers to improve sensory feel are selected from the group consisting: of polyethylene glycol, hydroxypropyl guar, guar hydroxypropyltπmomum chloπde, polyquaternary 3, 5, 6, 7, 10, 11 and 24 and mixtures thereof

Another highly prefeπed optional component of the present compositions are one or more humectants and solutes A vaπety of humectants and solutes can be employed and can be present at a level of from about 0 5 % to about 25%, more preferably from about 3 0 % to about 20 % The humectants and solutes are non-volatile, orgamc matenals hav g a solubility of a least 5 parts m 10 parts water A prefeπed water soluble, orgamc matenal is selected from the group consisting of a polyol of the structure

Rl - 0(CH₂ - CR2HO)_nH

where Rl = H, C1-C4 alkyl, R2 = H, CH and n = 1 - 200, C2-C 10 alkane diols, guanidine, glycohc acid and glycolate salts (e g ammonium and quaternary alkyl ammonium), lactic acid and lactate salts (e g ammonium and quaternary alkyl ammonium), polyhydroxy alcohols such as sorbitol, glycerol, hexanetπol, propylene glycol, hexylene glycol and the like, polyethylene glycol, sugars and starches, sugar and starch deπvatives (e g alkoxylated glucose), panthenol (including D-, L-, and the D,L- forms), pyrrolidone carboxylic acid, hyaluronic acid, lactamide monoethanolamine, acetamide monoethanolamine, urea, and ethanol amines of the general structure (HOCH2CH2)_xNH_v where x = 1-3, y = 0-2, and x+y = 3, and mixtures thereof The most prefeπed polyols are selected from the group consisting of glycerine, polyoxypropylene(l) glycerol and polyoxypropylene(3) glycerol, sorbitol, butylene glycol, propylene glycol, sucrose, urea and tπethanol amine

Prefeπed water soluble organic matenal are selected from the group consisting of glycerine, polyoxypropylene (1) glycerol and polyoxypropylene (3) glycerol, sorbitol, butylene glycol, propylene glycol, sucrose, and urea and tnethanolanune

The use of oil thickening polymers, such as those listed in EP 0 547 897 A2 to Hewitt, published 23/06/93, incorporated herem by reference, can also be mciuded in the water phase of the emulsions of the present invention

A vaπety of additional ingredients can be incorporated into the compositions of the present invention These matenals includmg, but not limited to, liquid appearance aids, salts and their hydrates and other "filler matenals" are listed U S Patent 5,340,492, to Kacher et al , issued August 23, 1994, and U S Patent No 4,919,934, to Deckner et al , issued Apπl 24, 1990, which is incorporated herem by reference

Other non limiting examples of these additional ingredients include vitamins and deπvatives thereof (e g , ascorbic acid, vitamin E, tocopheryl acetate, and the like), sunscreens, thickening agents (e g , polyol alkoxy ester, available as Crothix from Croda at levels up to 2% and xanthan gum at levels up to about 2%); preservatives for maintaining the anti microbial integrity of the compositions; anti-acne medicaments (resorcinol, salicylic acid, and the like); antioxidants; skin soothing and healing agents such as aloe vera extract, allantoin and the like; chelators and sequestrants; and agents suitable for aesthetic purposes such as fragrances, essential oils, skin sensates, pigments, pearlescent agents (e.g., mica and titanium dioxide), additives to impart a draggy rinse feel (e.g., fumed silica), additives to enhance deposition (e.g., maleated soybean oil at levels up to 3%), lakes, colorings, and the like (e.g., clove oil, menthol, camphor, eucalyptus oil, and eugenol).

II. Process for Preparing the Liquid Personal Cleansing Compositions Herein

To prepare the liquid personal cleansing compositions of the present invention, the encapsulated lipophilic skin moisturizing agent is prepared as hereinbefore described. The encapsulated lipophilic skin moisturizing agent is then mixed into die personal cleansing matrix, which contains the lathering surfactant, the stabilizer, water and any optional ingredients. The amount of stress that should be applied to the encapsulated lipophilic skin moisturizing agent particles as they are mixed into the personal cleansing matrix is an amount such that at least about 10% by weight of die encapsulated particles are nonspheπcal. The liquid personal cleansing matrix, to which the encapsulated lipophilic skin moisturizing agent is added, is prepared according to conventional methods for preparing liquid personal cleansing compositions.

III. Characteristics of the Liquid Personal Cleansing Compositions Herein

In order to achieve the deposition benefits hereinbefore described and to be consumer-acceptable, it is important that the liquid personal cleansing compositions of the present invention have certain rheological properties. In particular, die liquid personal cleansing compositions of the present invention have a viscosity ranging from about 2,000 cps to about 100,000 cps, preferably from about 5,000 cps to about 70,000 cps, more preferably from about 10,000 cps to about 40,000 cps, as measured by the Viscosity Method set forth hereinafter in the Analytical Methods section and a yield point ranging from about 5 to about 90 dynes/sq. cm., preferably from about 7 to about 50 dynes sq. cm, more preferably from about 9 to about 40 dynes/sq. cm. and most preferably from about 1 1 to about 30 dynes/sq. cm., as measured by the Yield Point Method set forth hereinafter in the Analytical methods Section.

The liquid personal cleansing compositions of the present invention provide clinically efficacious moisturization benefits to the skin. It is believed that this is due to the dramatically increased deposition of lipophilic skin moisturizing agent comprised of relatively large droplets compared to lipophilic skin moisturizing agents comprised of smaller droplets. The liquid personal cleansing compositions of the present invention have a Deposition Value of at least about 10 micrograms/square centimeter, preferably at least about 20 micrograms/ square centimeter, more preferably at least about 30 micrograms/square centimeter, as measured by the Deposition Method set forth hereinafter in the Analytical Methods section.

Analytical Methods

A number of parameters used to characterize elements of the present invention are quantified by particular experimental analytical procedures. Each of these procedures are described in detail as follows:

1. Consistency (k) and Shear Index (n) of the Lipophilic Skin Moisturizing Agent

The Carrimed CSL 100 Controlled Stress Rheometer is used to determine Shear Index, n, and Consistency, k, of the lipophilic skin moisturizing agent used herein. The determination is performed at 35°C with the 4 cm 2° cone measuring system typically set with a 51 micron gap and is performed via die programmed application of a shear stress (typically from about 0.06 dynes/sq. cm to about 5,000 dynes sq. cm) over time. If this stress results in a deformation of die sample, i.e. strain of the measuring geometry of at least 10-4 rad sec, men this rate of strain is reported as a shear rate. These data are used to create a viscosity μ Vs. shear rate γ' flow curve for the material. This flow curve can then be modeled in order to provide a mathematical expression that describes die material's behavior wid n specific limits of shear stress and shear rate. These results were fitted with die following well accepted power law model (see for instance: Chemical Engineering, by Coulson and Richardson, Pergamon, 1982 or Transport Phenomena by Bird, Stewart and Lightfoot, Wiley, 1960):

Viscosity, μ = k (γ')ⁿ"^

2. Viscosity of the Liquid Personal Cleansing Composition

The Wells-Brookfield Cone/Plate Model DV-II+ Viscometer is used to determine die viscosity of the liquid personal cleansing compositions herein. The determination is performed at 25°C with die 2.4 cm⁰ cone (Spindle CP-41) measuring system with a gap of 0.013 mm between tiie two small pins on the respective cone and plate. The measurement is performed by injecting 0.5 ml of the sample to be analyzed between the cone and plate and toating the cone at a set speed of 1 rpm. die resistance to die rotation of the one produces a torque that is proportional to die shear stress of die liquid sample. The amount of torque is read and computed by die viscometer into absolute centipoise units (mPa*s) based on geometric constants of die cone, die rate of rotation, and the stress related torque.

3. Deposition of the Lipophilic Skin Moisturizing Agent A. Preparation

The arms are washed witii a nonsoap-containing, nonlipid-containiπg product to reduce background interference as much as possible, then blotted dry. The subject then wets die entire surface of die inner forearm widi 95-100F tap water for five seconds. The subject then saturates a puff, such as that described in Campagnoli; U.S. Patent 5,144,744; Issued September 8, 1992, and allows die puff to drain for 10 seconds. One milliliter of the liquid personal cleansing composition which contains die lipophilic skin moisturizing agent is applied to the forearm of die subject and men die product is rubbed with die puff for 10 seconds to generate lather. The lather is allowed to remain on die forearm for fifteen seconds, followed by a thorough rinse for fifteen seconds widi the water flowing from inner elbow to wrist. The subject arm is uien pat dried wi i a paper towel. The subject then allows the arm to "air" dry for 30 seconds.

B. DEPOSITION PROTOCOL- SEBUMETER

Deposition of die lipophilic skin moisturizing agent on the skin is measured using a a Sebumeter SM810 which is commercially available from Courage and Khazaka GmbH. The Sebumeter measures die amount of lipophilic skin moisturizing agent mat has been deposited on die skin via photometry of a special plastic strip, which becomes transparent when it absorbs die lipophilic skin moisturizing agent. The plastic stnp is extended over a miπor which is connected to a spring. The measuring head of die device (comprised of spring, miπor and plastic strip) is pressed against die skin for 30 seconds. The Deposition Value (μ g/sq. cm) is indicative of the amount of lipophilic skin moisturizing agent on die skin; die Deposition Value increases widi increased amount of lipophilic skin moisturizing agent. The method is insensitive to humidity. Sebumeter readings (3) are taken along die length of die forearm and die Deposition Value (μg/sq. cm) is defined as die mean of die 3 readings, divided by a conversion factor to translate die sebumeter readings to actual deposition levels in μg sq. cm.

The Sebumeter has die following limitations:

1. The Sebumeter tape also detects natural skin lipids. A criterion of this test is that subjects baseline value measured on die Sebumeter, prior to washing, be less than or equal to 3 μg/sq. cm of forearm skin.

2. The Sebumeter like other surface extraction measurements may not measure all die deposited lipophilc skin moisturizing agent; if die skin topography is undulating it is possible iat deposited lipophilic skin moisturizing agent may not be extracted by die Sebumeter tape.

3. The Sebumeter tape becomes saturated at a Deposition Value of above about 300 μg/sq. cm; so this mediod can only measure deposition values up to about 300 μg/sq. cm.

4. Different lipophilic skin moisturizing agents will have different conversion factors. For testing non-petrolatum lipids, a new calibration curve is required.

C. Calibration To translate the Sebumeter data obtained as hereinbefore described into deposition data, it is necessary to generate a conversion factor. To generate the conversion factor, an extraction is done for each lipid system and die extracted sample is analyzed by gas chromatography. The extraction is done at die same time as the Sebumeter reading and is taken from die same forearm, die extraction procedure is as follows:

1) An open-ended glass cylinder (2 inches in diameter) is placed onto the subject's inner forearm and securely strapped in place.

2) Five ml of extraction solvent is added to the cylinder.

3) The liquid is stiπed on the subject's arm for 30 seconds using a blunt-ended glass stirring rod. The full surface area of die enclosed forearm is treated widi solvent.

4) The liquid is transfeπed to a 6 dram vial using a disposable transfer pipet.

5) Steps 2-5 are repeated two times (total of three samples, 15 ml of solvent collected)

The extracted sample is men analyzed by gas chromatography as follows:

APPARATUS

Gas Chromatograph HP 5890 or equivalent equipped widi capillary inlet system and flame ionization detector.

Integration System PEN Turbochrom v4.0 data system, or HP 3396 Series II integrator, or equivalent widi peak-grouping capability.

Column DB-5ht, 30 M x 0.32 mm I D., 0.10 μm film diickness, J&W Scientific cat. no. 123-5731.

Analytical Balance Capable of weighting to 0.0001 g.

Pipet 1 mL, Class A.

Volumetric Flask 1000 mL, 100 mL, glass stoppered.

Glass Syringe 100 μL capacity

Autosampler Vials With crimp-top caps

Dry Bath Regulated at 80 - 85°C

Pipettor Ependorf Repeator widi 12.5 mL reservoir

Stir Plate and Stir Bars Teflin-coated stir bars REAGENTS

Heptane ACS grade Squalane Aldnch cat no 23,431-1 or equivalent Lipid Standard GC CONDITIONS Carπer Gas Helium UHP grade or regular grade helium punfied dirough a dry tube and an oxygen scrubber Flow pressure regulated at 25 psi wid 25 ml/nun split

Injection Mode Sphtless

Injection Volume 2 μl

Injector Temperature 310°C

Oven Temperature 100°C for 0 minutes @ 10°C/mm to 350°C, hold for 6 mm Program

Detector Temperature 350°C

Hydrogen and Air Flows Optunized for gas chromatograph used

Bunching Factor 2

SOLUTIONS

Internal Standard Solution Into a clean, dry 100 mL volumetπc flask, analytically weight 0 1 g of squalane, recording weight to nearest 00002 g Dilut to volume with heptane, stopper and stir to dissolve (A 1 100 dilution of this solution can be used as die extraction solvent when generatmg samples )

Lipid Stock Solution Into a clean, dry 100 ml volumetπc flask, analytically weight 0 5 gram of lipid standard, recording weight to nearest 0 0002 g Dilute to volume with heptane, stopper and stir to mix

Lipid Working Standards Label tJiree autosampler vials as follows "100 μg," "300 μg" and "500 μg " Using die glass syringe, transfer 15 μL of internal standard solution mto each vial Rinse syringe well with heptane, then use it to transfer the following amounts of lipid stock solution to the vials

Std Vol Stock Soln (μL)

100 μg 20 300 μg 60 500 μg 100

Dilute to approx 0 5 mL wi i heptane, then cap and shake to mix

OPERATION

1 Calibration Run each standard under die above conditions Select die 10-14 largest peaks from die calibration run and create a peak group widun ύie calibration of die method Assign the amount of lipid m die standard to die group for each calibration level Plot the area ratio on the y-axis Do not force the line dirough the oπgin or include the oπgin The r2 value should be at least 0 9990 Check calibration every ten or twelve samples and at the end of die sample run

2 Sample Analysis Evaporate samples to dryness under a stream of dry nitrogen Reconstitute m 0 5 mL heptane Cap tightly and place on dry bath for 5 minutes, shake to dissolve completely Transfer to autosampler vials and analyze on calibrated instrument widi die proper ISTD amount entered Important Because die baseline is cluttered, manually check each result file for coπect peak identification

The GC data is dien plotted on a curve versus the Sebumeter data The slope of die curve is the conversion factor The conversion factor for petrolatum is 0 56

4 Filtrate weight of Polycation

The filtrate weight of a polycation is measured via a filtration apparatus which utilizes mechanical suction to effectively filter out die polycation coascervate

The complex coascervate is formed by mixing togedier dissolved polycation and dissolved sodium hexametaphosphate (Glass H from FMC Corporation - average P2O5 chain length of 21 The total amount of combined polycation and hexametaphosphate to be mixed togedier is 12 grams The ratio of polycation to hexametaphosphate to be employed is ratio at which a precipitate is formed When gelatm is the polycation, the ratio of gelatm to hexametaphosphate to be employed is 11 1 (e g , 11 grams of gelatm adn 1 gram of hexametaphosphate)

Once die proper amounts of polycation and hexametaphosphate to be mixed togedier has been calculated as descnbed above, both die polycation and die hexametaphosphate are dissolved in de-ionized water widi heatmg and stirrmg The total amount of water to be used for dissolving die polycation ad die hexametaphosphate is 286 grams The hexametaphosphate is dissolved 19x by weight water The polycation is dissolved in die remainder of the water After the polycation and die hexametaphosphate have been separately dissolved, die two solutions are mixed togedier. When gelatin is used as the polycation, die pH is then adjusted to 3.7 widi glacial acetic acid added drop-wise while stirring. The resultant mixture is then cooled to room temperature to induce a phase separated coascervate polycation/hexametaphosphate water complex which can be filtered and weighed.. The coascervate complex is filtered from die solution via a setup consisting of a 1000 ml Erlenmeyer Flask, 100 mm porcelain Buchner funnel, and 90 mm medium porosity/medium flow rate Whatman grade No. 40 filter paper. The mechanical suction is provided via a 1/6 horsepower Gast vacuum pump. The filtered coascervate complex is weighed and die weight is reported in grams as the filtrate weight of polycation.

5. Particle Size Distribution for Lipophilic Skin Moisturizing Agent Particles

The particle size distribution of die lipophilic skin moisturizing agent is estimated via a scanning laser microscope which is commercially produced by Lasentec (Lasentec Ml OOF). The Lasentec Ml OOF measures suspended particles by scanning a focused laser beam at a constant velocity across particles suspended in the liquid and moving past die window of a probe. When the focal point intercepts a particle, some light is scattered back to the probe and converted to an electronic pulse, which is converted to size by die relationship: d = v * t. The duration of die pulse represents the time (t) die particle is illuminated in die focal point. Because die velocity (v) of die focal spot is known, (d) is dierefore die scanned distance across die particle. This distance represents die length of a chord of die particle. The chord length distribution is an accurate direct measure of die particle structure dimensions and particle structure shate as determined on a 3 -dimensional basis. The Ml 00 classifies particles into 38 channels, ranging from 1.9 to 1000 microns. The particle size distribution is generated using a length cube weight average chord calculation which gives an estimate of the amount of substance per particle size (versus die number of particles per particle size):

∑»Λ⁴ i=l

Leng h Cube Weight Average Chord ι=l

n_j = Counts in an individual measurement channel

Mi = Midpoint of an individual channel k = Upper channel # (2 < k < 38)

The lasentec measures the particle size distribution of everyu ing widiin die formula including precipitates and air pockets. Therefore, light microscopy is used as a supplemental lipophilic moistunzmg agent particle size measurement technique to confirm die data generated by die Lasentec Ml OOF In dus technique, die product is viewed under very low magnification (<10X) between a plate and covers p and lipophilic moistuπzmg agent particles sizes are estimated via a micrometer

6 Yield Pomt of Liquid Personal Cleansing Compositions

The Cammed CSL 100 Controlled Stress Rheometer is used to determine the yield pomt of the liquid personal cleansmg compositions. As used herem, the yield pomt is the amount of stress required to produce a strain of 1% on die liquid personal cleansmg composition The determination is performed at 77°F widi the 4 cm 2° cone measuring system set widi a 51 micron gap. die determination is performed via die programmed application of a shear stress (typically from about 0 06 dynes/sq. centimeter to about 500 dynes/square centimeter) over time. If dus amount of stress results in a deformation of die sample, a shear stress vs. strain curve can be created. From this curve, the yield pomt of die liquid personal cleansmg composition can be calculated.

7 Strength of the Complex Coascervate A Preparation

The complex coascervate is formed by combining the formula amounts of die desired polycation and polyanion in aqueous solution When die polycation is gelatm, die pH is ad_justed to within die range of 3.5 to 4 5 by adding glacial acetic acid drop-wise The resultant mixture is cooled to induce a phase separated coascervate The supernatant is decanted, and enough of die complex coascervate is transfeπed to a petn culture dish (100 x 15 mm) to completely fill die dish and leave a flat surface flush widi die top of die dish The sample is diem allowed to equilibrate at room temperature for 24 hours

B Strength Protocol

The Stable MicroSystems Universal TA XT2 Texture Analyser and die XT RA Dimension data acquisition system is used to measure die strength of the complex coascervate. The Texture Analyser uses a cylindncal probe (14 x 11.5 mm) to measure force in compression of die complex coascervate The probe is set widiin 2 mm of the top of die complex coascervate sample. The probe pushes down to a tngger force of 5 grams at die speed of 1 mm/sec this is followed by a 4 mm compression distance at die entrance and exit speeds of 1 mm/sec The data acquisition system records die required force m compression versus time The maximum force in compression is recorded as die strength of the complex coascervate. 8. Method for Determining % Nonspherical Particles

A stereo binocular scope (Zeiss SV8) is utilized to determine die % nonspherical particles in die final product. Typically, pictures are taken of die final product at a magnification ranging from 9.5x to 24x. Using the pictures, die number of nonspherical particles (as hereinbefore defined) in the picture is counted. The % nonspherical particle is determined by dividing the number of nonspherical particles by die total number of particles.

Examples

The following shower gel compositions are non-limiting examples of die liquid personal cleansing compositions of die present invention.

Ingredients #1 Ul U3 M

Encapsulated Particles Pre-mix Composition:

Gelatin type A; 150 Bloom Strength 2.21 0.0 0.0 0.0

Gelatin type A, 100 Bloom Strength 0.0 2.21 0.0 0.0

Gelatin type A, 275 Bloom Strength 0.0 0.0 2.21 1.98

Hexameta Polyphosphate 0.20 0.20 0.20 0.18

Petrolatum 40.16 40.16 40.16 35.42

Glacial Acetic Acid (dropwise till pH < 4.4) -0.08 -0.08 -0.08 -0.08

De-ionized Water (Most in Excess) QS QS QS QS

Final Formula with Incorporated Filtered Particles:

Ammonium Lauryl Sulfate 2.14 2.14 2.89 4.3 Ammonium Lauredι-3 Sulfate 6.42 6.42 8.66 6.5 Sodium Lauroamphoacetate 3.67 3.67 4.95 4.7 Fatty Acid Soap 0.0 0.0 0.0 0.0 Laurie Acid 1.4 1.4 1.4 1.4 Trihydroxystearin 0.38 0.38 0.75 0.4 Optional Ingredients 4.53 4.53 4.39 5.0

Encapsulated Petrolatum Particles (from Pre- 23.57 23.57 16.4 11.0 mix) Water QS QS QS QS

Lather (Ultimate Volume) 450 450 390 550

Deposition (μg/cm^) 69 43 46 40

Particle size (at least 50% by weight of particles) >500 >500 >500 >600

(microns)

Viscosity (cp) 13,760 .. 20,100- 24,770 pH 5.5-6.5 5.5-6.5 5.5-6.5 5.5-6.5

Yield Point (dynes/sq. cm.) 10 — 14 18 Encapsulated Particles Pre-mix Preparation

1 Dissolve hexameta polyphosphate in 19 times as much water while stirring

2 Dissolve gelatm in remaining water and heat to 50-60°C while stirring in agitated tank

3 Heat lipophilic moistunzmg agent to 50-60°C

4 Add hot lipophilic moistunzmg agent at 50-60°C to gelatm-water solution at 50-60°C

5 Adjust agitation (RPM) to obtain desired particles size

6 Add polyphosphate-water solution to gelatin-water-lipophi c moistuπzmg agent dispersion

7 Add glacial acetic acid drop-wise until pH ranges from 3 8 to 5 0

8 Cool particle mixture while stirring pnor to mcorporation of encapsulated particles mto liquid personal cleansmg matnx

Incorporation of Encapsulated Particles mto Personal Cleansmg Matnx

The encapsulated lipophilic skm moistuπzmg agent particles are mixed mto die personal cleansmg matnx usmg a Kenics Static Mixer with a 1 5 mch diameter and 12 elements The flow rate is adjusted until die desired % nonsphencal particles is obtained (highly dependent on rheology)

Claims

What is claimed is;

1. A liquid personal cleansing composition characterized in that it comprises: a) a moisturizing phase comprising from 1% to 35% by weight of die composition of an encapsulated lipophilic skin moisturizing agent; wherein the lipophilic skin moisturizing agent is encapsulated within a complex coascervate comprising a polycation having a minimum filtrate weight of 10 grams and a polyanion, wherein said complex coascervate has a hardness ranging from 50 to 1400 grams force, and wherein die lipid skin moisturizing agent comprises droplets having a particle size distribution such diat at least 10% by weight of the droplets have a diameter of greater dian 100 microns; and b) an aqueous phase comprising: i) from 0.1 % to 10% by weight of die composition of a stabilizer; ii) from 5% to 30% by weight of the composition of a lathering surfactant; and iii) water.

2. A liquid personal cleansing composition characterized in that it comprises: a) a moisturizing phase comprising from 1% to 35% by weight of die composition of an encapsulated lipophilic skin moisturizing agent; wherein the lipophilic skin moisturizing agent is encapsulated widiin a complex coascervate comprising a polycation having a minimum filtrate weight of 10 grams and a polyanion, wherein the lipid skin moisturizing agent comprises droplets having a particle size distribution such diat at least 10% by weight of die droplets have a diameter of greater than 100 microns, and wherein die encapsulated lipophilic skin moisturizing agent is essentially free of cross-linking agent; and b) an aqueous phase comprising: i) from 0.1% to 10% by weight of die composition of a stabilizer; ii) from 5% to 30% by weight of the composition of a lathering surfactant; and iii) water.

3. A liquid personal cleansing composition according to any one of die preceding Claims which has a Deposition Value of at least 10 micrograms/square centimeter.

4. A liquid personal cleansing composition according to any one of ie preceding claims wherein at least 30% by weight of die encapsulated lipophilic skin moisturizing agent particles in die final product are nonspherical.

5. A liquid personal cleansing composition according to any one of die preceding claims wherein die complex coascervate comprises from 0.1% to 15% polycation and from 0.01% to 10% polyanion and wherein die ratio of the polycation to die polyanion in die complex coascervate ranges from 30:1 to 1:5..

6. A liquid personal cleansing composition characterized in diat it comprises: a) from 0.1 % to 5% of a polycation; b) from 0.01 % to 1 % of a polyanion; c) from 0.75% to 30% of a lipophilic skin moisturizing agent having a consistency ranging from 5 poise to 5,000 poise and a shear index ranging from 0.1 to 0.9 poise, wherein the lipophilic skin moisturizing agent has a particle size distribution such that at least 10% by weight of the droplets have a diameter greater than 100 microns; d) from 0.1% to 10% of a stabilizer; e) from 5% to 30% of a lauiering surfactant; and f) water; wherein the personal cleansmg composition has a viscosity ranging form 2,000 centipoise to 100,000 centipoise; wherein the ratio of polycation to polyanion ranges from 30: 1 to 1:5, and wherein die liquid personal cleansing composition is essentially free of cross- linking agent.

7. A liquid personal cleansing composition according to any one of die preceding claims wherein die polycation comprises gelatin.

8. A liquid personal cleansing composition according to any one of the preceding claims wherein die polyanion is selected from the group consisting of polyphosphate, gum arabic, sodium alginate and mixtures thereof.

9. A liquid personal cleansing composition according to any one of die preceding claims wherein at least 50% by weight of die particles comprising die lipophilic skin moisturizing agent have a droplet size greater dian 100 microns.

10. A liquid personal cleansing composition according to any one of die preceding claims wherein at least 50% by weight of die particles comprising the lipophilic skin moisturizing agent have a droplet size of at least 200 microns.

11 A method for preparing liquid personal cleansmg compositions charactenzed by

1) preparing an encapsulated lipophilic skm moistuπzmg agent wherem the lipophilic skm moistuπzmg agent is encapsulated widi a complex coascervate compnsed of a polycation havmg a minimum filtrate weight of 10 grams and a polyanion, and wherem die complex coascervate has a hardness rangmg form 50 to 1400 grams force, and

2) mixing the encapsulated lipophilic skm moistuπzmg agent to a liquid personal cleansmg composition matnx, wherem die final liquid personal cleansmg emulsion composition compnses a) from 1% to 35% encapsulated lipophilic skm moisturizing agent particles, b) from 0 1% to 10% of a stabilizer, c) from 5% to 30% of a lathering surfactant, and d) water, and wherem die final liquid personal cleansmg product contains a lipophilic skm moistuπzmg agent compnsed of droplets havmg a particle size distπbution such diat at least 10% by weight of die droplets have a diameter of greater dian 100 microns

12 A method according to any one of die preceding claims wherem at least 10% of the encapsulated lipophilic skm moistuπzmg agent particles m die final liquid personal cleansmg product are nonspheπcal

13 A method according to any one of die preceding claims wherem die lipophilic skm moistunzmg agent has a consistency rangmg from 5 to 5,000 poise and a shear mdex rangmg from 0 1 to 0 9

14 A meώod according to any one of die preceding claims wherem die lipophilic skm moistunzmg agent is compnsed of droplets havmg a particle size ώstπbution such diat at least 50% by weight of die droplets have a diameter of greater dian 100 microns

15 A mediod according to any one of hte preceding claims wherem the polycation is gelatm

16 A liquid personal cleansmg composition according to any one of die preceding claims wherem die polyanion is selected from the group consisting of polyphosphate, gum arable, sodium alginate and mixtures thereof

17. A method according to any one of die preceding claims wherein the complex coascervate has a hardness ranging from 400 to 1200 grams force.

18. A mediod according to any one of die preceding claims wherein the complex coascervate comprises from 0.1% to 15% polycation and from 0.01% to 10% polyanion and wherein die ratio of die polycation to die polyanion in die complex coascervate ranges from 30: 1 to 1:5.

19. A mediod according to any one of die preceding claims wherem the complex coascervate is essentially free of cross-linking agent.

20. A product prepared according to die process of any one of die preceding claims.