PIGMENTED COSMETIC COMPOSITIONS AND METHOD OF MAKING SAME

Abstract: Cosmetic formulations have activatable dormant pigments dispersed in an anhydrous base or vehicle. Shear forces applied to the cosmetic formulation following application to the skin causes activation of the dormant pigment thereby releasing the pigment and giving the original color of the anhydrous base or vehicle renewed intensity or a "long wearing" effect.

Description: PIGMENTED COSMETIC COMPOSITIONS AND ~ METHOD~OF ~ MAKI G SAME ' ' TECHNICAL FIELD The present invention relates generally to cosmetic preparations and more specifically, to novel pigmented compositions having "activatable" dormant colored particles or pigments dispersed throughout a cosmetic vehicle or base. The cosmetic vehicle or base may comprise lipstick, blush, face powder, foundation, eyeshadow or any other cosmetic preparation containing a colorant or pigment. In use, shear forces (e.g. rubbing onto the surface of the skin) activate the dormant color component causing a sustained release of pigment thereby giving the original color a renewed intensity or a "long wearing" affect. Alternatively, sustained release of the dormant pigment may lend an unusual but aesthetic look to the cosmetic base composition characterized by a juxtaposition of at least two or more different colors or by the creation of a new color comprising a blend of the original color and the released pigment. BACKGROUND ART U.S. Patent No. 3,947,571 relates to the use of a microencapsulated oil in lipstick. Moisture applied to the lips after the lipstick has been applied results in a sustained release of oil from the capsules thus imparting a shiny "wet" look to the lips. This patent does not suggest microencapsulating pigment per se, nor does it suggest activating an encapsulated or dormant pigment by effecting rupture of the microcapsules via applied shear forces in order to achieve a "long wearing" affect. U.S. Patent No. 4,752,496 relates to the microencapsulation of "never dry" or paste cosmetics using the well known coacervation technique. After encapsulation the "greasy" cosmetic is applied to a substrate and subsequently overlaid with a film forming agent. The substrate may be used as samples capable of being distributed to consumers through the mail , or on inserts in magazines. Although this patent does suggest microencapsulating a "l ipstick" formulation, it does not disclosj nor suggest microencapsul ation of a pigment in a cosmetic formulation (e. g. lipstick) for the purpose of rendering it dormant so that it subsequently may be activated to achieve a "long wearing" affect. An Information Bulletin published by Dow Coming (Form No. 24-550-88 ) entitled "Information About Specialty Copolymers" describes a highly cross-l nked polymethacrylate copolymer in the form of a fine particle-sized, freely flowing powder which may be used to absorb various l iquid systems both volatile and non-volatile used in cosmetic formulations. The Information Bulletin states that the Dow Corning polymer, sold under the designation POLYTRAP Q5-6603, may be spread into a thin film on a surface, such as rubbing on the skin, to cause the absorbed fluids to come into contact with such surface. The Dow Corning Information Bul letin however, fail s to suggest loading the poly¬ methacrylate copolymer with a pigment so that the latter may be rendered dormant until "activated" or released on a sustained basis for renewing the color i n a cosmetic formulation and achieving a '-'long wearing" affect. -2a- U.S. Patent No. 4,756,906 relates to a cosmetic colorant composition which relies on the use of microcapsules to add a second colorant to a first and different colorant. The intended effect of the added microcapsules is to render colored, highlight, or alter in color an existing color. That is, the intent is to effect a visible change in color. This intent is significantly different from providing a color identical or complementary to an original color to achieve a "long wearing" effect without any visible color change to the user. -3- Past attempts to provide acceptable cosmetic products having pigmented solid particles which may be activated or released on a sustained basis by the appl ication of shear forces thereby gi ving a renewed color intensity or "long wearing" look have not been successful . When pigments were microencapsul ated and pl aced di rectly into a cosmetic base, it was found that the microcapsules felt "gritty and hard" on the skin, thus rendering the composition unacceptable as a cosmetic product. Attempts to ameliorate thi s undesirable condition by mixing the sol id particles with oi l s or emollients of various types to form a dispersion al so resulted in failure by yiel ding microcapsules that were fragil e, and thus too easily rupturable during handling, or pigment concentrations insufficient to give the desi red renewed cc4βr intensity. When pigment was added to fine particle-size agglomerated powders combined with a cosmetic vehicle or base and then rubbed into the skin, intensification of color was inadequate to provide a "long wearing" affect. These disadvantages were overcome by the present invention when it was discovered that in a first form cosmetical ly acceptable compositions may be produced having microencapsulated pigmented solid particles by forming a dispersion of the pigment in a hydrophobic, non-vol atil e, low viscosity liquid carrier; coacervating the dispersion, to yield microcapsules in the form of a stabl e, freely flowing, dry powder; and then incorporating the microcapsules in a compatible anhydrous base or vehicle. In a second or alternatively preferred form of the invention, it was discovered that the pigment could be loaded onto a fine particle-size, hi gh surface area, solid substrate and then coated with an adherring oil or outer film to entrap the pigment on the substrate. When the resulting cosmetic compositions were applied to the skin and rubbed or otherwise subjected to shear forces, the microcapsules and/or entrapping substrate particles were readily -4- ruptured or otherwise mechanically distorted thereby releasing their intensely colored pigment and giving the compositions' color or shade a perceptible "long wearing" look. DISCLOSURE OF THE INVENTION Briefly described, the present invention contemplates cosmetic formulations having dispersed therein rupturable microcapsules the cores of which comprise pigmented solid particles dispersed in a hydrophobic, non-volatile, low-viscosity liquid carrier. The compositions are made by first forming the initial dispersion by mixing the pigmented solid particles with the liquid carrier, grinding the mixture to yield a uniform particle size distribution in the initial dispersion, and then microencapsulating the pigment/liquid carrier dispersion by coacervation to yield microcapsules in the form of a stable, free flowing, dry powder. The microcapsules then are further processed by being dispersed in a compatible cosmetic vehicle or base. In an alternative embodiment, the pigment is applied to an entrapping substrate in the form of fine solid particles having a high surface area. The pigmented substrate is then coated with a film thereby yielding a stable, free flowing, dry powder which may be further processed by being dispersed in a compatible cosmetic vehicle or base. BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to cosmetic formulations useful for imparting color to the surface of the skin. Such formulations, generally referred to as "makeup", may have many different forms -5- incl uding without l imitation l ipstick, foundation, face powder, blush, eyeshadow and so on. Each makeup form, i n turn, generally includes a color component in the form of pigmented sol id particles for giving it its characteristic color or "shade" , or other solid particles for giving it a desi red texture or sheen (mica, pearl escents, waxes, etc. ) with the color component bei ng dispersed throughout a suitable anhydrous base or vehicl e. For exampl e, in the case of "l ipstick" the coloring agent or pigmented ingredients may be dispersed i n a base comprising a mixture of waxes, emollients, and moisturizers, whereas, in the case of "blush", the pigmented solids may be dispersed i n a base comprising a mixture of talc, kaol in, and various known binders. In whatever form, the color or shade of a particular applied makeup formulation usually fades with time as the pigmented sol id particles are rubbed off or abraded during daily activity. It has long been a desi rabl e objective in the cosmetic arts to render the original application of makeup color "long wearing" or renewable on a sustained basis without reappl i cation. In order to meet this objecti ve of providing a cosmetic formulation having color renewable characteri stics thereby giving it the desi red "long wearing" look or qual ity, the present invention in a first preferred form contemplates di spersi ng the color component or pigmented sol id in a l iquid carrier, microencap¬ sulating the liquid carrier dispersion to form a stable, dry, free flowing powder and then combining the resulting microcapsules with other compatible ingredients of a particular cosmetic base or vehicle. . In forming the initial dispersion, a sel ected colorant in the form of pigmented solid particles is mixed with a suitable l i quid carrier in an amount ranging up to about 70% by weight of the total dispersion, i. e. the remainder of the dispersion comprises not less than about 30% by weight of the l iquid carrier. As will be made more apparent below, this ratio may be adjusted however, depending upon the type of pigment selected and the type of liquid carrier selected, it being critical only that the viscosity of the resulting dispersion be less than about 4000 cps when measured at room temperature (78°F) . An increase in the amount of pigment relative to the l iquid carier generally will result in an increase in the viscosity of the di spersion leading to microcapsules that are too hard and gritty, whereas a decrease in pigment relative to the liquid may result in microcapsules that are too easily rupturable, or to less than desirable intensity of the release ! pigment or color. When util izing a low viscosity l iquid carrier (e. g. mineral oi l ) a pigment/l iquid carrier ratio in the range of about 1 :2 to about 1 :1 has been found to achieve a good balance between color intensity, lack of "grittyness" and capsule integrity, and therefore, is mostly preferred. Suitable pigments may comprise any organic or inorganic pigment or colorant approved for use in cosmetics by the CTFA and the FDA such as the lakes, i ron oxides, titanium dioxide, i ron sulfides, or other conventional pigments used in cosmetic formul ations. Conventional approved dyes may also be used provided they are hydrophobic (water insoluble). The lakes (organic) and the i ron oxides are particularly preferred because of thei r excellent color intensity. The l iquid carrier component of the initial dispersion must be inert, hydrophobic (water insoluble ) and non-volatile, have a low viscosity and be capable of forming a colloidal suspension when the pigment granules are mixed therein. Any of the conventional oleophil ic -7- or oil compounds used in cosmetic formul ations such as mineral oil , vegetable oil , peanut oil , lanolin oi l , squalene, castor oi l , i sopropyl myri state, isopropyl palmitate, sil icone oi l , and di isopropyl dimerate, either alone or blended together, are suitable. However, because the viscosity of the initial dispersion prior to being microencapsul ated must be carefully controlled withi n the desired range mentioned above, it has been found that a l ight or low viscosity mineral oil provides the best results. In thi s regard, a l ight mineral oi l sold by Witco, Petroli a, Pa. , under the designation "Carnation White Mineral Oil " is mostly preferred. Nonetheless, it will be appreciated that the other oil compounds mentioned above as well as those commonly used in the cosmetic arts may be employed instead so long as thei r vi scosity is modified or controlled sufficiently to form a dispersion having a vi scosity not more than about 4000 cps when measured at room temperature. In accordance with the invention, the pigmented sol id components and the liquid carrier are mixed together at room temperature in a conventional mixing kettle and then passed one or more times through a conventional grinding mil l (e. g. a "stone" mill ) until the resulting dispersion has a rich, creamy consistency with high gloss. Sufficient grinding of the dispersion will be achieved when a sample thereof measured on a standard Hegeman gauge reads no less than 6 1 /2 indicating a maximum particle size of less than 20 microns. Since gri nding of the pigment/l iquid carrier phase in the grinding mill will tend to increase somewhat the vi scosity of the dispersion; and furthermore, si nce the particle size of different pigments vary, it will be necessary to adjust the pigment/oil ratio up or down depending upon the different pigments -8- employed for a given liquid carrier. This is illustrated in Table 1 below which shows the relative proportions of pigment and liquid carrier by percent weight which must be employed to achieve ground dispersions within the desired viscosity range comprising a range of different preferred pigments and the preferred liquid carrier (Carnation White Mineral Oil), respectively. [SEE NEXT PAGE] TABLE I 3 © o DISPERSION PIGMENT % PIGMENT % CARRIER* VISCOSITY(cp D_C Red 7 Calcium Lake 40 60 1550 D*C Red 30 Talc Lake 33 67 3500 oo I D_C Red 6 Barium Lake 45 55 1800 Russet Iron Oxide 50 50 2200 Yellow Iron Oxide 40 60 2500 Brown I on Oxide 50 50 2000 ♦ Carnation White Mineral Oil VO o ON -9- Whichever preferred pigment of Table 1 is util ized, it wil l be appreciated that the initial dispersion is characterized by a vi scosity of less than about 4000 cps when measured at room temperature (78°F) , substantially uniform particle size distribution less than about 20 microns, and a substantially complete wetting of each particle by the liquid carrier (i. e. no agglomeration). In accordance with the invention, the ground pigment/l iquid carrier dispersion is microencapsulated to form stable , dry, free flowing powder of micro-sized particles whose diameter ranges from about to about 20 microns . It has been found that microcapsules having a diameter larger than 20 microns results in an unacceptable cosmetic product by feeling rough or gritty on the skin. The preferred method of microencapsul ation is by the technique of coacervation. Under thi s method, which is well known and understood, a l iquid dispersion is emul sified in a continuous, external aqueous phase to form micro-sized droplets and a complex of colloidal material added to the external phase is reacted upon in such a way to form a deposit on and around each droplet thereby forming an outer wall or shel l . In the present case, the preferred colloids forming the outer wall or shel l of each icrocapsule comprise, gelatin and gum arabic, the internal phase or core of which comprises the pigment/l iquid carrier dispersion. After formation of the outer shell s, the temperature of the aqueous coacervating sol ution is lowered causing gel ation and hardening of the shell wall material . Further hardening may be accomplished by treating with a condensate polymer (e. g. urea formaldehyde) and applying a cross-l inking agent (e. g. glutaraldehyde) to some or all of the available amino sites on the surface of the gel atin/gum arabic wal l . - 1 0- Polymerization Induced by the cross-l inking agent causes the capsul e' s wall to harden sufficiently so that the microencapsules may be removed from the continuous external phase and dehydrated to form a stabl e, dry, free flowing powder capable of bei ng handled easily and further processed to make cosmetic products without undue rupture of the microcapsules. When the preferred coacervation method i s used to form the microcapsules, the size of the cores, as well as the wall thickness and strength of the outer wall s or shells, may be controlled precisely by altering such factors as the ph of the aqueous phase, the rel ati ve concentration of the colloids in the aqueous phase, the degree of agitation of the coacervation sol ution, the temperature and duration of the reaction, the degree of cross-l i nking, and so on, all as is fully known and understood in the art. Accordingly, these detail s form no part of and are outside the scope of the present invention. Suffice it to say, in practicing the invention, the initial pigment dispersion is microencapsulated to form capsules ranging in size from about 2 microns to about 20 microns, wherein the internal phase or core of pigment/oil preferrably compri ses from about 80% to about 90% of each capsule by weight; the outer shell components, i. e. gelatin and gum arabic, each comprises about 3% to about 5% by weight; the condensate polymer (urea formaldehyde) comprises about 4.00% to about 8.00% by weight; and the cross-linking agent (glutaraldehyde) comprises about 0.10% to about 0.50% by weight. It has been found in accordance with the invention that microcapsules of the foregoing composition containing a core of pigment dispersed in a l i quid carrier wherei n the resulting dispersion has a - 1 1 - viscosity of less than about 4000 cps when measured at room temperature are easily rupturable when subjected to shear forces (e. g. rubbing on the skin, eating, stroking of the cheeks, etc. ), yet are capable of mai ntai ning thei integrity and withstanding rupture duri ng the handl ing and processing steps necessary to form the novel cosmetic formul ations contemplated herei n. The process of microencapsulation by coacervation is more fully described in the '496 Patent cited above, column 7, l ine 33 et seq. , which patent and particularly the portion thereof describing "coacervation" being incorporated herein by this reference. The interested. reader also is directed to U.S. Patent No. 2,800,457, and U.S. Patent No. 3,190,837 , each of which further describes the detail s of the preferred coacervation microencapsulation technique, and each of which al so is incorporated herein by this reference. Following microencapsulation, the encased pigment/oil dispersion, now in the form of an easily handled, stabl e, dry free flowing powder is added to a compatible, anhydrous vehicle or base to form cosmetic product ' s having a "long wearing" or renewable color characteristic. Owing to the relati vely hi gh concentration of pigment in each microcapsule core, a surprisingly smal l amount of microencapsul ated pigment is necessary 1n each cosmetic vehicle to provide high intensity color reπewabil ity when the microcapsules are "activated" , i. e. ruptured by bei ng subjected to shear forces. In making a preferred form of "long wearing" l ipstick, for exampl e, about 5% of the l ipstick base by weight may compri se microencapsulated pigment according to the invention. In a preferred formula for a "l ong wearing" powder blush, the -12- microencapsulated pigment content may be about 10% of the vehicle by weight. Nonetheless, it will be understood that as much microencapsulated pigment may be added to a selected cosmetic vehicle or base as desired so long as the cosmetic form in question is still capable of being applied to the skin and the microcapsules do not feel granular or are otherwise apparent. In general, the particular preferred amount of microencapsulated pipent employed may range up to about 60% of the base vehicle with an amount in the range of about 2% to about 20% being mostly preferred. In use, light rubbing of the cosmetic preparation after application, or movement of the skin resulting from normal daily activities (e.g., smiling, pursing of the lips, eating, kissing, stroking of the cheeks) activates new color by causing rupture of the microcapsules and a release of pigment into the cosmetic base sufficient to produce a perceptible "long wearing" affect. The following Examples further illustrate the invention without limiting same wherein all quantities as stated are by weight percent. EXAMPLE I A pigmented oil dispersion in accordance with the invention was formulated as follows: 40.00000% DSC Red No. 7 Calcium Lake 60.00000% Mineral Oil (Carnation White) Total 100.00000% The following procedure was utilized. The pigment was added to the mineral oil in a Hobart Mixer and blended for 20 minutes at room temperature. The mixture was then passed through a Stone Mill twice (2X) and tested on a Hegeman gauge for particle fineness. The gauge -13- reading was 6 1 /2 indicating that no pigment particle dispersed in the mineral oil was larger than 20 microns. The consistency of the dispersion appeared rich and creamy with high gloss indicating a complete wetting of the pigment particles by the mineral oi l with no agglomeration. The viscosity of the dispersion at room temperature measured 1550 cps on a Brookfield Model RVT vi scometer. EXAMPLE I I The dispersion or pigment grind of Example I was microencapsulated using a standard coacervation technique. The resulting microcapsules were less than 20 microns in diameter and were formul ated as follows. 84.90000% Pigment Dispersion (Example I ) 3.50000% Gel atin 4.00000% Gum Arabic 6.00000% Urea Formaldehyde Polymer 0.10000% Gl utaraldehyde 1.50000% Sil ica Total 1 _-. _--_ The microcapsules were in the form of a stable, dry, free flowing powder and although readily rupturable by l ight rubbing against the skin, they maintained thei r integrity duri ng normal handli ng. [SEE NEXT PAGE] -14- EXAMPLE III The microcapsules of Example II were added to a "lipstick" formulation as follows: 38.00000% Castor Oil 10.00000% Di isopropyl Dimerate 8.00000% Isostearyl Neopentanoate 5.00000% Candelilla Wax 3.50000% Isopropyl Lanolate 4.50000% Lanolin 3.50000% Beeswax 10 3.00000% Microcrystalline Petroleum Wax 3.00000% PPG -5 Lanolin Wax 2.00000% Carnauba Wax 1.50000% Polybutene 13.00000% Colorants 5.00000% Encapsulated Pigment (Example II) Total Tϋ ϋϋϋϋϊ The followT g process was utilized. A vessel was charged with the waxes (candelilla, beeswax, microcrystalline petroleum wax and carnauba) and brought up to 200°F. In a separate vessel the -20 diisopropyl dimerate, isostearyl neopentanoate, lanolin, isopropyl lanolate, lanolin wax, and polybutene were added together and blended under medium speed conditions at a temperature of 175°F. When the waxes were at 200°F in the first vessel they were added to the second vessel under conditions of medium speed mixing. The colorants were ground in the castor oil in a three-roll mill to a fineness of 61/2 or greater on the Hegeman gauge and added to the second vessel and mixing was continued until the colorants were completely dispersed. The temperature of the second vessel was reduced to 170°F followed by the addition of the microencapsulated pigment while medium speed mixing was 30 continued until the microcapsules were completely dispersed. The mixture was then removed from the second vessel, poured into molds, passed through a cooling tunnel maintained at a temperature in the -15- range of 35-42°F, extracted from their molds, and flamed to produce lipsticks. A lipstick from the batch was applied to the lips of a subject and shear forces applied via normal activity, i.e. pursing of the lips, eating, drinking, smiling, and talking. The shear forces induced by such activity to the lip region caused a quantity of the microcapsules to rupture, thereby releasing additional color on the lips. As a result, color intensity remained for a longer duration compared to lipsticks that did not contain the microencapsulated pigment. EXAMP E IV The following formulation was used to make "blush" utilizing the microencapsulated pigment of Example II. 23.00000% Mica 22.00000% Talc 9.00000% Neopentaglycol Dicapryl Dicaprate 9.00000% Bismuth Oxychloride 4.00000% Calcium Stearate 1.50000% Calcium Silicate 1.50000% Synthetic Wax (and) Corn Gluten Protein 0.60000% Wool Wax Alcohols 0.25000% DAC Red 7 Calcium Lake 3.75000% DAC Red 6 Barium Lake 0.19000% Iron Oxide Red 0.04000% Iron Oxide Yellow 0.13000% D&C Red 6 Barium Lake 10.04000% Timiron MP-1001 15.00000% Microencapsulated Pignent (Example II) Total lύύ.όόόόϋt The "blush" was made in accordance with the following procedure. The talc, colorants, calcium stearate, calcium silicate and bismuth oxychloride were added to a mixing vessel and blended together under high speed conditions to thoroughly intermix the ingredients at room -16- temperature. The mixing vessel consisted of 24 l iter NOVA Model Baker-Perkins disperser/granulator havi ng a 12-inch impeller driven at 360 rpm and a high speed granul ator blade driven at 3000 rpm. The ingredients were removed from the mixing vessel and pulverized in a MIKROPUL mlcropulverizer to reduce the particle size of the ingredients to less than about 10 microns. The pulverized ingredients were returned to the main mixing vessel and mica was added under high speed blending conditions. The wool wax alcohol s and neopentaglycol dicapryl dicaprate were mixed together in a separate jacketed kettle and the temperature was increased to 175°F. The heated mixture was sprayed under a pressure of 50 psi Into the main mixing vessel while high speed mixing conti nued- The blended ingredients were removed from the mai n kettle and pulverized once again to insure a thorough dispersion of the oil s in the particulate ingredients. The pulverized ingredients were returned to the main mixing vessel and the microencapsul ated pigments added under continuous high speed mixing until evenly dispersed throughout the blend. The intermixed ingredients were removed and compressed into a shallow pan on an ALITE powder press. The blush was applied from the pan via a brush applicator to the cheeks of a subject. As a resul t of normal dally activity e. g. smili ng, eating, talking and stroki ng the cheeks, a quantity of microcapsules were ruptured thereby releasing additional color to the cheeks. The additional color provided more intense color and a perceived long lasting affect compared to blush made in accordance with the same formulation, but not contai ning any microencapsul ated pipent. - 1 7- EXAMPLE V A pigmented oil dispersion in accordance with the invention was formul ated as follows : 50.00000% Russet Iron Oxide 50.00000% Mineral Oil (Carnation White) Total 100.00000% The followi ng procedure was employed. The pigment was added to the mineral oil in a HOBART Mixer and blended for 20 minutes at room temperature. The mixture was then passed through a stone mill twice (2X) and tested on a Hegeman gauge for particle fineness. The gauge reading was 6 1/2 indicating that no pigment particle dispersed in the mineral oil was larger than 20 microns. The consistency of the dispersi on appeared rich and creamy , with hi gh gloss indicating a complete wetting of the pigment particles by the mineral oil with no agglomeration. The vi scosity of the dispersion at room temperature measured 2200 cps on a Brookfield Model RVT viscometer. EXAM LE VI The dispersion or pigment gri nd of Example V was microencapsulated using a standard coacervation technique. The resulting microcapsules were less than 20 microns in diameter and were formulated as follows : 84.90000% Pigment dispersion (Example V ) 3.50000% Gel atin 4.00000% Gum Arabic 6.00000% Urea Formal dehyde Polymer 1.50000% Sil ica 0.10000% Gl utaraldehy e Total lOO.OόόόOt -18- EXAMPLE VII The following formul ati on was used to make "eyeshadow" util izing the microencapsulated pigment of Example VI. 2.75000% Mica 5.00000% Zinc Stearate 1.50000% Sil ica 10.00000% Synthetic Wax (and) Corn Gl uten Protein 1.02000% Black Iron Oxide ljO 0.50000% Cosmetic Red Iron Oxide 0.68000% Chromi um Hydrate Green 20.40000% T.mica Brillant Gold 29.75000% Timica Sil k White 3.40000% Timiron Super Gol d 10.00000% Decyl 01 e ate 15.00000% Microencapsulated Pigment (Example V I ) Total lϋODϋϋϋϊ The "eyesRadow" was made in accordance with the following procedure. The colorants, zinc stearate and sil ica were added to a mixing vessel and blended together under high speed conditions to thoroughly intermix 0 the ingredients at room temperature. The mixing vessel consisted of a 24 liter NOVA model BAKER-PERKINS disperser/granulator havi ng a 12-i nch impel ler driven at 360 rpm and a high speed granul ator bl ade driven at 3000 rpm. The ingredients were removed from the mixing vessel and pul verized in a MIKR0PUL micropul verizer to reduce the particle size of the ingredients to less than about 10 microns. The pulverized ingredients were returned to the main mixing vessel and mica was added under hi gh speed blending conditions. The decyl oleate, synthetic wax and corn gl uten protein were placed in a separate jacketed mixing kettle 0 and the temperature increased to 175°F. The heated oil /wax mixture then was sprayed under a pressure of 50 psi into the mai n mixing vessel while high speed blending continued for two minutes to disperse the oi l /Wax throughout the powdered i ngredients. The blend was removed from -19- the main mixing-vessel and pulverized once again to assure a thorough dispersion of the oils in the particulate ingredients. The pulverized, dispersed ingrodients were then returned to the main mixing vessel and the microencapsulated pigment added under continuous high speed blending to disperse the microencapsulated pigments throughout the blend. The blend was removed and compressed into a shallow pan on an Alite Powder Press. The eyeshadow in the pan, which had a beige color, was applied via a brush to the eyelids of a subject. After rubbing with a sponge tipped applicator to induce rupture of a quantity of microcapsules, the original beige color changed to a deep bronze color and the intensity of the new color appeared to be greater than the original color. EXAMPLE VIII A lipstick was made in accordance with the following formulation utilizing the process described above in connection with Example III. 43.00000% Castor Oil 10.00000% Di isopropyl Dimerate 8.00000% Isostearyl Neopentanoate 5.00000% Candelilla Wax 4.50000% Lanolin 3.50000% Isopropyl Lanolate 3.50000% Beeswax 3.00000% Microcrystalline Petroleum Wax 3.00000% PPG-5 Lanolin Wax 2.00000% Carnauba Wax ' 1.50000% Polybutene 13.00000% Colorants Total 100.00000% [See Next Page] -20- The lipstick material was melted down in a jacketed kettl e and microencapsulated usi ng a standard coacervation technique. The resulting microcapsules were added to the above l ipstick formula at 10 percent by wei ght and an equi valent amount of castor oi l was removed. The procedure of Example III was again followed to make lipstick having the 10 percent encapsul ated l ipstick ingredient therein. A sample of the resulting l ipstick was appli ed to the l ips of a subject and normal activity simulated. Although a certain amount of capsules were ruptured and additional color was released on the l ips, the color i ntensity was too low to give any percei ved l ong weari ng affect. Moreover, an unpleasant, rough feel ing was perceived upon application? and the encapsulated material left an unpleasant gritty residue on the l ips. In view of these factors, the formul ati on of this Example was considered not to be an acceptable cosmetic product. The foregoing Examples illustrate how in accordance with the present invention microencapsulation i s effective to render the activatable pigment dormant in the host cosmetic formul ation. Nonetheless, other means suitable for maki ng the pigment dormant and activatable by shear forces may be empl oyed instead without departing from the pri nciples of the invention. Thus, in an alternatively preferred embodiment of the invention, it has been found that the pigment to be released on a sustai ned basis may be rendered activatable by entrappment on or within a sol id substrate combined with the cosmetic vehicle or base in question. The preferred entrapping medium compri ses a fine particle-sized, sol id particul ate that i s inert, hydrophobic, and insolubl e and which contai ns many pores or sites givi ng it a hi gh surface area per unit volume. In general , any particul ate approved for -21 - use in cosmetics and meeting the foregoing criteria is suitabl e. Examples include polymethacrylate copolymers, sil ica beads, and porous nylon powders with the polymethacryl ate copolymer sold by Dow Corning under the designation POLYTRAP Q5-6603 bei ng mostly preferred. The mostly preferred entrapping medi um consists of micro-sized particles of copolymer pressed together to form agglomerates (20-80 microns ) which, in turn, are loosely clustered into aggregates of 200 to 1200 microns in size. The copolymer i s available in the form of a stable , dry free flowing powder facil itating its use in cosmetic formul ations. Any of the pigments or dyes mentioned above may be loaded onto the polymethacrylate copolymer agglomerates by mixi ng the colorants with the copolymer powder i n a suitable blender such as a Baker-Perkins disperser/granul ator. In general , 1 to 2 parts pigment per part of copolymer are mixed together. It is bel ieved that the pigment mechanically attaches to the irregular copolymer surface and lodges in the nooks and crannies thereof rather than be absorbed as in the case of l iquid systems being loaded onto the copolymer. In order to maintain the pigment or colorant stable on the copolymer, in accordance with the invention, a thin film or layer is appl ied to the pignent loaded copolymer subtrate. Generally, any non-volatile, oleophilic l i quid approved for use in cosmetics is suitable for thi s purpose such as the - oil compounds mentioned above in connection with the fi rst preferred form of the Invention with the light (low viscosity) mineral oil such as the "Carnation White" form available from Witco bei ng mostly preferred. The amount of l iquid adherent is not critical so long as a sufficient amount i s present to completely wet the pigment particles on the copolymer surface with due al lowance being gi ven for the high absorbtion -22- capabil ity of the particul ate. Generally from .2 to 1.4 parts of l iquid adherent to 1 part pigment is suitable. Based upon the copolymer content, the liquid adherent should range from about .25 to 1.0 parts for each part of the copolymer. The l i quid adherent may be added to the pigment/copolymer blend in a standard mixer and blended thoroughly to disperse the li quid throughout the sol ids. If desired, suitable processing aids such as fumed sil ica may be added to the pigment before the liquid is added. After mixing these ingredients together, the pigment entrapped copolymer will be in the form of a stabl e, dry, free flowi ng powder. The pigment entrapping powder may then be added to a conventional , compatibl e, anhydrous cosmetic base or vehicle as in the first embodiment to produce cosmetic formulations contai ning "activatabl e" dormant pigment suitable when activated or released to give the formulation a "long weari ng" affect regarding its color or shade. In use, a sl ight rubbing of the cosmetic formula into the skin will tend to rupture or otherwise mechanically distort the aggregated polymethacrylate copolymer material thereby releasing and spreading the pigment/liquid adherent dispersion on the surface of the skin, thus activating the colorant and gi ving the formul ati on its "long wearing" or renewed color characteristic. The same results may be achieved by applying other shear forces, say, in the case of l ipstick, for exampl e, those occassioned by eating, pursing of the lips, kissing, smiling, and so on. The foregoing alternatively preferred form of the invention will now be further illustrated by the fol lowing Examples which are not to be construed as limiting and wherei n all stated quantities are by percent weight. -23- EXAMPLE IX A stable, dry, free flowing powder comprising a pigment loaded substrate was prepared having the following formulation: 29.00000% D&C Red 7 Calcium Lake 1.00000% Silica - Fumed 40.00000% Polymethacrylate* 30.00000% Mineral Oil (Carnation White) Total 100.00000% * Dow Corning POLYTRAP Q5-6603 The following procedure was utilized. The pigment and silica-fumed were blended together in a 24 liter NOVA model BAKER-PERKINS disperser/granulator under high speed conditions for three minutes. This mixture was then micropulverized to a particle size than about 10.0 microns using a MIKROPUL icropulverizer. The pulverized blend was returned to the mixing vessel and aggregates of polymethacrylate (800 to 1200 microns) were added while high speed blending continued for an additional one minute to break down the aggregates and evenly disperse the pigment throughout the mixture. The mineral oil was then sprayed into the mixing vessel at room temperature under 50 psi pressure while high speed blending continued for an additional one minute to thoroughly coat and wet the pigment and polymethacrylate blend. The mixture was then passed through the MIKROPUL micropulverizer to further assure that the oil was thoroughly adsorbed onto the surface of the substrate material thereby entrapping the pigment thereon. The final mixture was in the form of a pigmented, stable, dry, free flowing powder. -24- EXAMPLE X A "lipstick" was made in accordance with Example III, but for the substitution of the entrapped, pigmented powder of Example IX in lieu of the encapsulated pigment powder, i.e. the entrapped, pigmented powder (Example IX) comprised 5% by weight of the lipstick formulation of Example III. The lipstick was formulated following the procedure of Example III. A lipstick from the batch was applied to the lips of a subject and shear forces applied via normal activity, i.e. pursing of the Hps, eating, drinking, smiling and talking. The shear forces Induced by such activity to the lip region caused a quantity of the entrapped pjjjment to be released, thereby providing additional color. As a result, the color intensity remained for a longer duration compared to lipsticks that did not contain the entrapped pigment blend. EXAMPLE XI A powder "blush" was made in accordance with Example IV, but for the substitution of the entrapped, pigmented powder of Example IX in lieu of the encapsulated pignent powder, i.e. the entrapped, pi ented powder (Example IX) comprised 15% by weight of the blush formulation of Example IV. The same procedure as in Example IV was followed. The blush was applied from the pan via a brush applicator to the cheeks of a subject. As a result of normal daily activity, e.g. smiling, eating, talking and stroking the cheeks, a quantity of the entrapped pigment was released, thereby, providing additional color. The newly released pigment provided more intense color and a perceived longer lasting affect compared to blush made in accordance with the same formulation, but not containing the entrapped pigment. -25- EXAMPLE XI I A stable, dry, free flowing powder comprising a pigment loaded substrate was prepared havi ng the following formulation : 29.00000% Russet Iron Oxide 1 .00000% Sil i ca-f umed 40.00000% Polymethacryl ate* 30.00000% Mineral Oil (Carnation White ) Total lϋ rø? * Dow Corning P0LYTRAP Q5-6603 The procedure of Example IX was util ized. EXAMPLE XIII A p ow_er "eyeshadow" was made in accordance with Example VII , but for the substituti on of the entrapped, pigmented powder of Exampl e XII in li eu of the encapsulated pigment powder, i .e. the entrapped, pigmented powder (Example XII ) comprised 15% by weight of the eyeshadow formulation of Example VII. The same procedure as Example VII was fol lowed. The eyeshadow in the pan, which had a beige color, was applied via a brush applicator to the eyel ids of a subject. After rubbing with a sponge tipped appl icator to induce release of the entrapped pigment, the or ginal bei ge color changed to a deep bronze color and the intensity of the new color appeared to be greater than the ori ginal color. [See Next Page] -26- EXAMPLE XIV A stable, dry, free flowing powder comprising a pipent loaded substrate was prepared having the following formulation: 37.31000% DAC Red #7 Ca Lake 1.50000% Silica-fumed 37.31000% Lecithin Treated Silica Beads 23.88000% Mineral Oil (Carnation White) Total lϋ ϋϋϋOI The procedure of Example IX was utilized, but for the substitution of micron-sized lecithin treated silica beads for the aggregates of polymethacrylate. The silica beads were obtained from U.S. Cosmetics Corp., Putnam, Conn. EXAMPLE XV A powder "blush" was made in accordance with Example IV, but for the substitution of the entrapped, pigmented powder of Example XIV in lieu of the encapsulated pigment powder, i.e. the entrapped, pigmented powder (Example XIV) comprised 15% by weight of the blush formulation of Example IV. The blush was applied from the pan via a brush applicator to the cheeks of a subject. As a result of normal daily activity, e.g. smiling, eating, talking and stroking the cheeks, a quantity of the entrapped pigment was released, thereby, providing additional color. The newly released pigment provided more intense color and a perceived longer lasting affect compared to blush made in accordance with the same formulation, but not containing the entrapped pigment. -27- EXAMPLE XVI A stable, dry, free flowing powder comprising a pigment loaded substrate was prepared having the following formulation: 43.95000% DAC Red #7 Ca Lake 1.10000% Silica-fumed 44.00000% Porous Nylon Powder 11.00000% Mineral Oil (Carnation White) , Total lϋ Oϋδϋf The procedure of Example IX was utilized, but for the substitution of porous nylon powder for the aggregates of polymethacrylate. The nylon powder (99% passing through a 400 mesh (38 micron) screen) was obtained from the Torey Company, New York, New York EXAMPLE XVII A powder "blush" was made in accordance with Example IV, but for the substitution of the pigment entrapped powder, of Example XVI in lieu of the encapsulated pigment powder, i.e. the pigment entrapped powder, (Example XVI) comprised 15% by weight of the blush formulation of Example IV. The blush was applied from the pan via a brush applicator to the cheeks of a subject. As a result of normal daily activity, e.g. smiling, eating, talking and stroking the cheeks, a quantity of the entrapped pignent was released, thereby, providing additional color. The newly released pigment provided more intense color and a perceived longer lasting affect compared to blush made in accordance with the same formulation, but not containing the entrapped pigment. -28- In carrying out the present invention it will be appreci ated that cαπbinations of the alternatively preferred forms as described above may be employed in a single cosmetic vehicle or base. Thus, where it is desi red to achieve a dormant pigment palette compri sing both intense and subtle colors in the same vehicl e, the encapsul ated pigment of the fi rst form of the invention (which provides an intense burst of color when activated) may be mixed with the entrapped substrate of the second form (which provides a more gradual shading of color when acti vated) in the same vehicle empl oying the rel ati ve proportions necessary to obtain the 10 precise effect or palette sought. Thi s yet further preferred form of the Inventi on will now be illustrated by the fol lowing Example which i s not to be construed as limiti ng and wherei n all stated quantities are i n percent weight. EXAWLE XVIII The encapsulated pigment of Example II was combined with the pigment entrapped substrate of Example XI to form a powder "blush" having the following formulation : ' 30.00000% Mica ?n 22.00000% Talc u 9.00000% Neopentaglycol Dicapryl Dicaprate 9.00000% Bismuth Oxychloride - 4.00000% Calcium Stearate 1.50000% Calci um Sil icate 1.50000% Synthetic Wax (and) Corn Gluten Protei n 0.60000% Wool Wax Alcohol s 0.25000% D_C Red 7 Calcium Lake 3.75000% D&C Red 6 Bari um Lake 0.19000% Iron Oxide Red 0.04000% Iron Oxide Yellow 0.13000% D&C Red 6 Barium Lake 10.04000% Timi ron MP-1001 3.00000% Microencapsulated Pigment (Example II ) 5.00000% Entrapped Pigment (Example IX ) Total 100.00000% -29- The powder "blush" was made util izing the procedure of Example IV. The blush was applied from the pan vi a a brush applicator to the cheeks of a subject. As a result of normal daily activity e. g. smil ing, eating, talking and stroking the cheeks, a quantity of the microcapsules and/or entrapped pigments were ruptured thereby releasing additional color to the cheeks. The additional color provided more intense color and a percei ved long lasting affect compared to the blush made in accordance with the same formulation, but not contai ning any microencapsulated and/or entrapped pigment. Moreover, the resulting palette of renewable color compri sed two components, i . e. an intense component and a more subtl ey shaded component. It i s evident from the foregoi ng that the present invention in its broadest sense contempl ates the provi si on of an activatabl e dormant pigment in a cosmetic formulation wherei n activation of the dormant pigment by appli ed shear forces releases color into the formul ation thereby renewing the original color of the formulation with the same or a different shade and gi ving the formulation a "long wearing" affect with regard to color. By encapsulating the pigment or entrapping it on a substrate as disclosed hereinabove the pigment is rendered inacti ve or dormant until the application of shear forces. Thus, the term "activatabl e" as used in the specification and claims means the release of the pigment from its dormant state in the cosmetic formulation to an acti ve state where it renews, reinforces, or enhances the intensi ty of the ori ginal color, or it juxtaposes a new or different color relative to the original color thereby producing striking and aesthetic effects. -30- Although different forms of the present invention have been fully described above with reference to actual Examples thereof, thi s was done merely for the sake of illustrating preferred embodiments of the invention as requi red by statute. Obviously, many changes, modifications, and alterations may be made without departi ng from the pri nciples of the invention. Accordingly, it i s desi red " that the present invention be l imited only by the true spi rit and scope of the annexed claims.

Claims: -31- hat is claimed is: 1. A color-sustainable cosmetic formulation which com¬ prises: a base phase having a characteristic color; and a dormant pigment dispersed in said base phase and being activatable when subjected to physical forces so as to sustain said characteristic color of said base phase. 2. The color-sustainable cosmetic formulation of claim wherein said dormant pigment is disposed in capsules dispersed said base phase. 3. The color-sustainable cosmetic formulation of claim wherein said dormant pigment is entrapped on solid substrates dispersed in said base phase. 4. The color-sustainable cosmetic formulation of claim wherein a first portion of said dormant pigment is disposed in capsules dispersed in said base phase and a second portion of said dormant pigment is entrapped on solid substrates disperse in said base phase. -32- 5. A color-sustainable cosmetic formulation which com¬ prises: a base phase having a characteristic color; and a dormant pigment activatable when subjected to physical forces so as to sustain said characteristic color of said base phase, said activatable dormant pigment being disposed in capsules dispersed in said base phase, each said capsule containing said dormant pigment and being rupturable when subjected to said physical forces. 6. The color-sustainable cosmetic formulation of claim 5 wherein said dormant pigment in certain of said capsules is dif ferent from a base pigment in said base phase. 7. The color-sustainable cosmetic formulation of claim 5 wherein said dormant pigment is dispersed in a liquid which is inert, hydrophobic, non-volatile, and has low viscosity. 8. The color-sustainable cosmetic formulation of claim 7 wherein said liquid is selected from the group consisting of mi eral oil, vegetable oil, squalene, castor oil, isopropyl myri- -33- state, isopropyl palmitate, peanut oil, lanolin oil, silicone oil, diisopropyl dimerate, and combinations thereof. 9. The color-sustainable cosmetic formulation of claim wherein said liquid includes mineral oil. 10. The color-sustainable cosmetic formulation of claim wherein each said capsule has a core comprising up to 70% pigm by weight. 11. The color-sustainable cosmetic formulation of claim wherein said dormant pigment comprises up to about 60% of said base phase by weight. 12. The color-sustainable cosmetic formulation of claim wherein the amount of said dormant pigment dispersed in said b phase is in the range of about 2% to about 20% by weight. 13. The color-sustainable cosmetic formulation of claim wherein said base phase comprises a color cosmetic selected fr the group consisting of lipstick, foundation, face powder, blu and eyeshadow. -34- 14. The color-sustainable cosmetic formulation of claim 13 wherein said base phase is lipstick. 15. The color-sustainable cosmetic formulation of claim 13 wherein said base phase is blush. 16. The color-sustainable cosmetic formulation of claim 5, wherein the size of each said capsule is in the range of about 2 to about 20 microns. 17. A color-sustainable cosmetic formulation which com¬ prises: a base phase having a characteristic color; and a dormant pigment being activatable when subjected to physical forces so as to sustain said characteristic color of said base phase, said dormant pigment being deposited on a solid substrate and coated with a liquid. 18. The color-sustainable cosmetic formulation of claim 17 wherein said solid substrate comprises micron-sized particles -35- selected from the group consisting of polymethacrylate, silica, porous nylon, and mixtures thereof. 19. The color-sustainable cosmetic formulation of claim 1 wherein said solid substrate is polymethacrylate. 20. The color-sustainable cosmetic formulation of claim 1 wherein said liquid is selected from the group consisting of mi eral oil, vegetable oil, squalene, castor oil, isopropyl myrist ate, isopropyl j palmitate, peanut oil, lanolin oil, silicone oil diisopropyl dimerate, and combinations thereof. 21. The color-sustainable cosmetic formulation of claim 1 wherein said dormant pigment is deposited on said solid substra in an amount of about 0.5 part to about 1.0 part by weight of said dormant pigment for each part by weight of said solid substrate. 22. The color-sustainable cosmetic formulation of claim 1 wherein said liquid is coated on said dormant pigment and said solid substrate in an amount of about 0.6 to about 0.9 part by weight for each part by weight of said solid substrate. -36- 23. A color-sustainable cosmetic formulation which comprises: a base phase having a characteristic color; and a dormant pigment being activatable when subjected t physical forces so as to sustain said characteristic color of said base phase, said dormant pigment including a first portio disposed in capsules dispersed in said base phase, and a secon portion deposited on a solid substrate and coated with a liqui 24. The color-sustainable cosmetic formulation of claim wherein said dormant pigment in certain of said capsules is different from a base pigment in said base phase. 25. The color-sustainable cosmetic formulation of claim wherein said dormant pigment is dispersed in a liquid which is inert, hydrophobic, non-volatile, and has low viscosity. 26. The color-sustainable cosmetic formulation of claim 2 wherein said liquid is selected from the group consisting of m eral oil, vegetable oil, squalene, castor oil, isopropyl myris -37- ate, isopropyl palmitate, peanut oil, lanolin oil, silicone oi diisopropyl dimerate, and combinations thereof. 27. The color-sustainable cosmetic formulation of claim wherein said liquid includes mineral oil. 28. The color-sustainable cosmetic formulation of claim wherein each said capsule has a core comprising up to 70% pigm by weight. 29. The color-sustainable cosmetic formulation of claim wherein said dormant pigment comprises up to about 60% of said base phase by weight. 30. The color-sustainable cosmetic formulation of claim wherein the amount of said dormant pigment dispersed in said b phase is in the range of about 2% to about 20% by weight. 31. The color-sustainable cosmetic formulation of claim wherein said base phase comprises a color cosmetic selected fr the group consisting of lipstick, foundation, face powder, blu and eyeshadow. -38- 32. The color-sustainable cosmetic formulation of claim 3 wherein said base phase is lipstick. 33. The color-sustainable cosmetic formulation of claim 2 wherein the size of each said capsule is in the range of about to about 20 microns. 34. The color-sustainable cosmetic formulation of claim 2 wherein said solid substrate comprises micron-sized particles selected from the group consisting of polymethacrylate, silica, porous nylon, and mixtures thereof. 35. The color-sustainable cosmetic formulation of claim 3 wherein said solid substrate is polymethacrylate. 36. The color-sustainable cosmetic formulation of claim 2 wherein said dormant pigment is deposited on said substrate in amount of about 0.5 part to about 1.0 part by weight of dormant pigment for each part by weight of said solid substrate. -39- 37. The color-sustainable cosmetic formulation of claim 2 wherein said liquid is coated on said dormant pigment and said solid substrate in an amount of about 0.6 part to about 0.9 par by weight for each part by weight of said solid substrate. 38. A method for making a color-sustainable cosmetic form lation which comprises: providing a base phase having a characteristic color; and dispersing in said base phase a dormant pigment being activatable when subjected to physical forces so as to sustain said characteristic color of said base phase. 39. The method defined by claim 38 which further com¬ prises: dispersing dormant pigment in a liquid; grinding said dispersed dormant pigment to form a dispersi having maximum particle size of less than about 20 microns; and encapsulating said dispersion to form rupturable capsules. 40. The method defined by claim 38 which further com¬ prises: -40- mixing said dormant pigment with micron-sized solid sub¬ strates; and coating said pigment and substrate mixture with an oleo¬ philic liquid to entrap said dormant pigment on said solid substrates. 41. The method defined by claim 38 which further comprise providing said dormant pigment by said method of claim 39 and said method of claim 40. 42. A method for sustaining the characteristic color of a cosmetic formulation applied to the skin which comprises: applying to a person's skin a cosmetic formulation includi a base phase having a characteristic color, and a dormant pigme dispersed in said base phase and being activatable when subject to physical forces; and applying physical forces to said cosmetic formulation to activate said dormant pigment so as to sustain said character¬ istic color.

Inventors: MARTIN SHARI R, PAHLCK HAROLD E, SQUIRES MICHAEL E, MARTIN, SHARI, R., PAHLCK, HAROLD, E., SQUIRES, MICHAEL, E.
Applicants: AVON PROD INC, AVON PRODUCTS, INC.
Application year: 1990
Main classification: A61K7
IPC codes: A61K8, A61Q1