WO1999055292A1 - Nail polish compositions - Google Patents

Abstract

The present invention relates to the field of cosmetics and especially to pigmented nail polish compositions having high gloss, good coverage, and superior film properties. In particular, the invention relates to nail polish compositions comprising a film forming polymer, a volatile liquid diluent, and a pigment, which exhibit a defined Gloss Value and Coverage Factor. The invention also relates to nail polish compositions comprising a film forming polymer, a volatile liquid diluent, and a pigment, wherein at least about 80 volume % of the pigment has a Wet Particle Size of less than 1000 nm. The invention further relates to methods of preparing pigmented compositions suitable for use in or as a nail polish comprising a pigment and a diluent, comprising the steps of: (a) providing an agglomerated powdered pigment having a primary particle size of from about 20 nm to about 200 nm as determined by microscopy; (b) air milling the agglomerated pigment to reduce the pigment particle size and to fracture at least a portion of the primary pigment particles; (c) combining the pigment from step (b) with a non-shear inducing, liquid diluent; and (d) dispersing the pigment in the diluent such that at least about 80 volume % of the pigment has a Wet Particle Size of less than 1000 nm.

Description

NAIL POLISH COMPOSITIONS

TECHNICAL FIELD The present invention relates to the field of cosmetics and especially to pigmented nail polish compositions having high gloss, good coverage, and superior film properties.

BACKGROUND OF THE INVENTION

Consumers wear nail polish to achieve a desired appearance, e.g., color, gloss, matte (diffuse look), coverage, evenness, wear, etc. Pigments are used extensively in nail polishes to achieve a desired color and appearance.

Unfortunately, while providing color and coverage, pigments tend to negatively impact gloss, evenness and wear properties.

It has now been discovered that nail polishes containing pigment, wherein at least about 80 volume %, preferably at least about 99 volume %, of the pigment has a Wet Particle Size of less than 1000 nm, provide desirable optical and mechanical properties to the resultant nail polish film (i.e., less than about 20 volume %, preferably less than about 1 volume %, of the pigment has a Wet Particle Size of 1000 nm or more). In particular, such compositions provide improved gloss, coverage, and toughness.

SUMMARY OF THE INVENTION The present invention relates to nail polish compositions comprising a film forming polymer, a volatile liquid diluent, and a pigment, wherein at least about 80 volume % of the pigment has a Wet Particle Size of less than 1000 nm. The invention also relates to nail polish compositions comprising a film forming polymer, a volatile liquid diluent, and a pigment, which exhibit a defined Gloss Value and Coverage Factor.

The invention further relates to methods of preparing pigmented compositions suitable for use in or as a nail polish comprising a pigment and a volatile liquid diluent, comprising the steps of: 2

(a) providing an agglomerated powdered pigment having a primary particle size of from about 20 nm to about 200 nm as determined by microscopy;

(b) air milling the agglomerated pigment to reduce the agglomerated pigment particle size and to fracture at least a portion of the pigment particles; (c) combining the pigment from step (b) with a non-shear inducing, liquid diluent; and

(d) dispersing the pigment in the diluent such that at least about 80 volume % of the pigment has a Wet Particle Size of less than 1000 nm.

DETAILED DESCRIPTION OF THE INVENTION The essential components of the present invention are herein described below. Also included are non-limiting descriptions of various optional and preferred components useful in the compositions of the present invention.

The present invention can comprise, consist of, or consist essentially of any of the required or optional components and/or limitations described herein. In the description of the invention various embodiments and/or individual features are disclosed. As will be apparent for the skilled practitioner all combinations of such embodiments and features are possible and can result in preferred executions of the invention.

All percentages and ratios are calculated by weight unless otherwise indicated. All percentages are calculated based on the total composition unless otherwise indicated.

All component or composition levels are in reference to the active level of that component or composition, and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources.

Referred to herein are trade names for materials including, but not limited to, polymers and optional components. The inventors herein do not intend to be limited by materials under a certain trade name. Equivalent materials (e.g., those obtained from a different source under a different name or catalog (reference) number) to those referenced by trade name may be substituted and utilized in the compositions herein. 3

Active and other ingredients useful herein may be categorized or described herein by their cosmetic and/or therapeutic benefit or their postulated mode of action. It is to be understood that the active and other ingredients useful herein can in some instances provide more than one cosmetic and/or therapeutic benefit or operate via more than one mode of action. Therefore, classifications herein are made for the sake of convenience and are not intended to limit an ingredient to the particularly stated application or applications listed.

All documents referred to herein, including all patents, patent applications, and printed publications, are hereby incorporated by reference in their entirety. The compositions of the present invention are suitable for application to animal nails, including human nails. The compositions of the present invention are useful, for example, for providing aesthetic, cosmetic, therapeutic, and/or prophylactic benefits to the nails. As used herein, the term "nail polish" is a comprehensive term describing a nail polish composition, product (including coloring products), or the like, which is useful for providing, for example, aesthetic, cosmetic, therapeutic, and/or prophylactic benefits to the nails.

As used herein, the term "animal nail" means a keratinaceous plate present at the upper surface of the end of a finger or toe of a primate or the analogous claw, hoof or the like of other animals. As used herein, the term "suitable for application to animal nails" means that the compositions are suitable for use in contact with animal nails without undue toxicity, incompatibility, instability, allergic response, and the like in regard to a given animal species. Preferred compositions are those suitable for application to human nails. In addition to natural nails, the compositions herein may also be used for application to synthetic (artificial) nails. Film-forming polymer

The nail polish compositions of the present invention comprise one or more film-forming polymers. Preferred nail polish compositions comprise from about 1%, more preferably from about 2%, even more preferably from about 5%, most preferably from about 10% film forming polymer, to about 50%, more preferably to 4

about 40%, most preferably to about 30% film forming polymer. Particularly preferred nail polish compositions comprise from about 6% to about 28%, more preferably from about 7% to about 28%, even more preferably from about 11% to about 25%), most preferably from about 14% to about 24% film-forming polymer, by weight of the composition.

Intermediate slurry compositions described herein preferably comprise from about 0.1%) to about 20%, more preferably from about 1% to about 12%, and most preferably from about 4%> to about 10%> film-forming polymer, by weight of the composition. Nitrocellulose is the preferred film-forming polymer for intermediate compositions.

Non-limiting classes of suitable film-forming polymers include solvent- borne polymers, water-borne polymers, and mixtures thereof. As used herein, the term "water-borne", with reference to a film-forming polymer, means that the polymer was prepared in a mixture comprising water and is preferably added to the composition which it comprises as a mixture (generally a dispersion) in water. Preferred film-forming polymers herein are solvent-borne polymers. As used herein, the term "solvent-borne", with reference to a film-forming polymer, means that the polymer was prepared under substantially anhydrous conditions and is preferably added to the composition which it comprises as a substantially anhydrous solution (or other mixture, whether heterogeneous or homogeneous, preferably homogeneous).

As used in reference to a composition suitable for application to the nails, or other composition, a solvent-borne composition means that the composition comprises one or more organic solvents and is substantially anhydrous, preferably containing less than about 50% water, more preferably less than about 25% water, even more preferably less than about 2% water, most preferably less than about 1% water (e.g., less than about 0.25% water). Solvent-borne compositions are preferred.

The term "film-forming polymer" means a homopolymer, copolymer, or mixture thereof which, as recognized in the polymer arts, forms an adherent continuum from a composition when applied to a substrate (in the present invention, nails). See, e.g.. Polymer Colloids, Robert M. Fitch, ed., New York: Plenum Press, 5

pp. 173-183 (1971). As used herein, the term "copolymer" includes linear, block, branched, graft, comb, and star copolymers. Preferred film-forming polymers are self-curing polymers. That is, they do not require chemical reaction or introduction of energy (e.g., exposure to ultraviolet rays) to form the adherent continuum. The film-forming polymers herein can be selected from nonionic, ionic

(anionic or cationic), and amphoteric (including zwitterionic) polymers. Anionic polymers are preferred for water-borne compositions.

Suitable film-forming polymers include any such as are known in the art, such as cellulosic polymers, polyacryls, polymethacryls, styrene-acryl copolymers, polystyrenes, polysiloxanes, polyesters, urethanes, urethane-acryl copolymers, siloxane-urethane copolymers, silicone-acryl copolymers, vinyl acetate polymers, and mixtures thereof. Preferred compositions comprise one or more cellulosic polymers, one or more polyurethanes, or a mixture thereof. The composition preferably comprises at least one cellulosic polymer and at least one polyurethane. The film-forming cellulosic polymers may be selected from polymers derived from cellulose such as are known in the art, including but not limited to cellulose esters. Preferred cellulosic polymers are nitrocellulose, nitrocellulose esters such as cellulose acetate butyrate, cellulose acetate propionate, and mixtures thereof. More preferred are nitrocellulose, cellulose acetate butyrate, cellulose acetate propionate, and mixtures thereof. Nitrocellulose polymers are most preferred. Exemplary nitrocellulose polymers are nitrocellulose RS types (nitrogen content of 11.5-12.2%)) of Hercules, such as nitrocellulose - RS Vi second, - RS ^lA second, - RS 1/8 second, - RS 1/16 second or the like.

The compositions hereof preferably comprise a total of from about 5%> to about 20%, more preferably from about 6%> to about 20%>, even more preferably from about 10%> to about 17%, most preferably from about 13% to about 16%, cellulosic polymer.

Preferred polyurethanes are selected from aromatic polyether polyurethanes, aliphatic polyether polyurethanes, aromatic polyester polyurethanes, aliphatic polyester polyurethanes, aromatic polycaprolactam polyurethanes, aliphatic polycaprolactam polyurethanes, urethane acryl copolymers, siloxane-urethane 6

copolymers, and mixtures thereof. More preferred are aromatic polyether polyurethanes, aliphatic polyether polyurethanes, aromatic polyester polyurethanes, aliphatic polyester polyurethanes, aromatic polycaprolactam polyurethanes, aliphatic polycaprolactam polyurethanes and mixtures thereof. Aromatic polyether polyurethanes, aliphatic polyether polyurethanes, aromatic polyester polyurethanes, aliphatic polyester polyurethanes and mixtures thereof are even more preferred. Aliphatic polyether polyurethanes, aliphatic polyester polyurethanes, and mixtures thereof are most preferred.

Preferred solvent-borne polyurethanes include Sanres EX519^®, Sanres EX499^® (hexylene glycol/neopentyl glycol/IPDI [isophorone diisocyanate] copolymer), Sanres 12711^®, Sanres 6010^®, and Sanres 6012^® (all of which are available from B.F. Goodrich). The most preferred polyurethane is Sanres EX519^®.

Preferred polyurethanes are those having a number average molecular weight of from about 10,000 to about 80,000, more preferably from about 15,000 to about 50,000, most preferably from about 20,000 to about 35,000.

The present compositions preferably comprise a total of at least about 1.25%) film forming polyurethane, e.g., at least about 2%, 3%>, 3.5%> or 5% film-forming polyurethane. The present compositions more preferably comprise a total of from about 1.25% to about 8%>, even more preferably from about 1.5% to about 5%>, most preferably from about 2% to about 4%, film-forming polyurethane.

In compositions comprising a polyurethane and a cellulosic film forming polymer, the composition preferably contains up to about 10%, e.g., up to about 5% or 4%, film-forming polymer other than polyurethane and cellullosic film forming polymer. Volatile diluent

The compositions hereof also contain a carrier which is suitable for application to the nails. The carrier comprises a liquid diluent system comprising a volatile organic solvent, water, or a mixture thereof. Organic solvents are preferred and can be used singly or in admixture. Preferred diluent systems solubilize (i.e., dissolve) the film forming polymers and dry in a reasonable time on nails. 7

Preferred volatile organic solvents have a boiling point at 1 atm of from about 50 °C to about 140 °C, more preferably from about 56 °C to about 125 °C. Preferred organic solvents are selected from alcohols, esters, ketones, aromatic hydrocarbons, aliphatic hydrocarbons, ethers, and mixtures thereof (more preferably C,-C₁₀, most preferably C₂-C₄). Alcohols and esters are more preferred, esters being most preferred. Preferred alcohols are monohydric. Preferred monohydric alcohols are ethanol, wo-propanol, and «-propanol. Preferred esters are butyl-, ethyl-, isopropyl- and propyl-acetate, and mixtures thereof. More preferred esters are ethyl acetate, butyl acetate, isopropyl acetate, and mixtures thereof Other non-limiting examples of suitable organic solvents are benzyl alcohol, amyl acetate, acet,heptane, wo-butyl acetate, toluene, methyl acetate, wo-butanol, /7-amyl alcohol, «-butyl alcohol, hexane, and methyl ethyl ketone.

The present compositions preferably comprise from about 55% to about 90%, more preferably from about 62% to about 78%, most preferably from about 66% to about 74%, liquid diluent, more preferably volatile, organic solvent.

8

Submicrometer Pigment

The nail polish compositions of the invention also comprise pigment particles having a Wet Particle Size of less than 1000 nm (1 micrometer), according to the method described herein below. Preferably, at least about 80 vol%, more preferably at least about 99 vol%>, of the total pigment in the composition has a Wet Particle Size of less than 1000 nm. Without intending to be bound by theory, it is believed that this particle size distribution contributes to the gloss improvements of the present invention. Especially preferred are compositions wherein the pigment consists essentially of solid, spherical particles and has a Wet Particle Size of from about 250 nm to about 750 nm.

The present nail polish compositions comprise from about 0.1% to about 10%, preferably from about 0.25% to about 5%, more preferably from about 0.5% to about 2% of pigment. Intermediate slurries hereof generally comprise up to about 20% pigment, preferably from about 5%> to about 15% pigment. As used herein, "pigment" means particulate materials which impart color or opacity to the composition, as well as other particulate material such as clay. Inorganic pigments, organic pigments, and mixtures thereof such as are known in the art are suitable for use herein. Suitable pigments are inorganic or organic pigments known as, for example, the FD&C and D&C colors, lakes, and iron oxides. Such pigments are disclosed in the C.T.F.A. Cosmetic Ingredient Handbook, First Edition, 1988. Organic pigments include, for example, D and C Red, Nos. 10, 11, 12, and 13, D and C Red No. 7, D and C Red Nos. 5 and 6, D and C Red Nos. 30 and 34, lacquers such as D and C Yellow No. 5 and D and C Red No. 2, and guanine, FD&C red #6 lake, FD&C red #7 lake, and other organic lakes. Inorganic pigments include, for example, titanium dioxide, bismuth oxychloride, brown iron oxide, the red iron oxides, the black iron oxides, mica, clay and the like. The pigments may be modified, e.g., by hydrophilic or hydrophobic treatment.

A preferred pigment is derived from agglomerated dry pigments which are reduced to the desired particle size distribution by a process comprising air milling the agglomerated pigment followed by wet milling the resultant air-milled pigment. 9

According to this preferred embodiment, the selection of agglomerated pigment is based on the primary particle size as well as the strength of the agglomeration. Agglomerated pigments having weak agglomerating strength and a primary particle size in the submicrometer range are preferred. The agglomerating strength must be sufficiently weak to permit sufficient separation of the particles by the process described herein.

The particle size of the agglomerated pigment is typically from about 1 micrometer to about 1 ,000 micrometers, as determined by conventional microscopic methods. For achieving high gloss, preferred agglomerated pigments are those commercially available as SOFT-TEX from Sun Chemical of Cincinnati, Ohio. Preferred pigments, including SOFT-TEX pigments, have a primary particle size of from about 20 nm to about 200 nm, as determined according to conventional microscopic techniques. For purposes of the hiding power of the nail polish, the primary particle size of the agglomerated pigment is preferably from about 200 nm to about 500 nm, as determined according to conventional microscopic techniques.

The agglomerated pigment is first air milled to reduce the particle size and/or to fracture (introduce flaw or crack) at least a portion of the pigment particles to facilitate their further size reduction in the wet milling step. This air milling step is important for providing the final submicrometer particle size distribution. The ability of the agglomerated pigment particles to be broken up in the air mill step depends on the strength of the agglomerated particle and the processing methods. A variety of air milling processes such as are known in the art may be used, provided that the process has sufficient force to induce fracture in at least a portion of the particles. Suitable air-mill processes include jet milling, hammer milling, ball mill, stir ball mill and combinations thereof.

Jet milling is preferred. As is known in the art, in jet mill processes particles are accelerated (e.g., jet speeds of up to about Mach 2), and ground in a high velocity fluid stream, effecting a communition either by means of mutual collision or impact against a target. The capacity and the effectiveness of the jet mill depend on the jet speed, i.e., the pressure and temperature of the incoming jet stream, which can be readily regulated by those skilled in the art. 10

Loop-type jet mills can be used. Such mills typically comprise a feeder device, feed nozzles (for feeding the starting pigment into the mill), grind fluid nozzles (for a feeding a fluid which transports the starting pigment into and throughout the mill), a flat-cylindrical grind chamber (for separating and/or fracturing the agglomerated pigment), and a collection chamber (for collecting the pigment after milling). The grind chamber typically comprises slots and a grinding wall. The collection chamber generally comprises a cyclone, a collection jar or container, and a fluid release bag/fine collection bag. An example of a laboratory size mill of this type is the Model 0 jet mill manufactured by Fluid Energy Aljet of Plumsteadville, PA, USA, having 2 grinding nozzles and one feed nozzle.

In the Model O jet mill, it is preferred that both grinding nozzles are set to about 100 +/- 10 psi and the feed nozzle is set to about 85 +/- 10 psi. The mill is preferably operated at ambient temperatures, of about 25 +/- 5 °C. The mill is set up and operated in order to obtain a good vacuum at the feed opening, to thereby enhance particle flow. Once the pressure is set, the feed nozzle can be moved in or out of the feed chamber in order to obtain a good vacuum at the feed nozzle.

A fluid gas for carrying the particles through the mill is injected into the chamber through the grinding nozzles. The fluid gas should be inert with respect to the particles being milled as well as to the metal of the mill, and is typically compressed nitrogen.

The particles to be milled are fed from the feeding device into the mill through the feed nozzles, generally in a manner to ensure continuous uniform feed flow. The Model O jet-mill has a vibration-feeding device, which is typically set at a feed rate of about 30-40 on the Model-O dial. With highly cohesive or wet pigments the feed chamber may tend to clog such that the feed rate may need to be decreased and/or the feed chamber cleared out. The fineness of the jet-milled particles is influenced by the amount of feed, with coarseness increasing with feed amount. For the Model O Jet-mill, the feed rate is preferably from about 80 to about 150 grams/hour, more preferably about 100 grams per hour. The particles enter the grinder chamber in a uniform stream through the slots distributed around the periphery of the chamber. The particles are reduced in size 11

and/or fractured by mutual collision or impact against the wall of the grinding chamber. The tangential arrangement of the jets in the Model O jet-mill induce a spiral air classification, which allows the finer particles to be drawn out of the mill while coarser powders continue to be ground at the outer part of the chamber. The expanded compressed air developed in the chamber transports the ground pigment out of the mill into the collection chamber. The fluid leaving the mill and carrying the particles enters the cyclone, where the coarse particles fall into the collection container and the fine particles are carried with the fluid into the collection bag. Depending on the size of the batch and the size of the collection container, the collection container may need to be replaced or emptied several times throughout the jet milling process. Typically when the collection container is replaced or emptied the collection bag should also be emptied, adding the contents of the bag to the contents of the collection container. The particles collected in the bag are typically finer particles than in the collection container, which are typically have a particle size range of about 1 micron or less.

If pigments are going to be milled individually it is not necessary to pre-mix the pigment. Where a mixture of pigments is to be used, e.g., to obtain a certain shade, the pigments are preferably pre-mixed prior to jet-milling. However, any mica or clay is preferably not pre-mixed since milling tends to destroy the properties provided by these ingredients.

To pre-mix, any mixer suitable for obtaining a homogenous pigment mixture can be used. For example, on a lab scale, high speed mixers such as a standard residential food blender (e.g., Osterizer brand) can be used. The mixer container and batch size are selected to enable the pigments to flow in the container, e.g., such that the container is from about ^lA to % full of the pigment. Where an Osterizer blender is used, the pigments are mixed on the highest speed ("liquefy") for approximately 30 seconds. If needed, the sides and bottom of the container are scraped to remove any powders that have not been thoroughly mixed. The mixing process is repeated until a homogeneous mixture is obtained. After the jet-milling process, the cyclone separates the particles into a fine stream, typically having a particle size of less than 1000 nm, and a coarse stream, 12

typically having a particle size of about 1000 nm, both of which are significantly smaller than the original agglomerated pigment. As will be understood in the art, both streams may contain agglomerated pigment. After jet-milling, the coarse particles are relatively easily reduced in size by wet milling. The particles obtained from jet-milling (fine and coarse) are then wet-milled.

Without intending to be bound by theory, it is believed that wet-milling reduces the particles to a narrow submicrometer size distribution and increases pigment stability.

Prior to wet-milling, the air-milled pigment is combined with a suitable liquid diluent system. A variety of diluents can be used, provided that it does not induce shear aggregation of the particles (where the final composition includes a shear aggregation-inducing ingredient, such as water and/or polyurethane, the ingredient is preferably formulated into the composition after the wet-milling step). Preferred diluent systems enhance the shearing and compacting forces created by interaction of the particle surfaces during milling, thereby enhancing particle fracture and/or break-up of agglomerates Preferred diluents are non-thixotropic.

The diluent system for wet-milling can comprise one or more of the liquid diluents suitable for application to the nails, described above. Accordingly, the diluent system can comprise one or more organic solvents intended to be present in the final nail polish composition. The nail polish composition per se, or a slurry which can be used in nail polish compositions, can be wet milled.

The Viscosity of the mixture to be wet-milled should be about 2500 centipoise or less at a 250 inverse seconds shear rate. The Viscosity can be determined by using a controlled stress rheometer. A RheoStress RS 100 rheometer made by HAAKE, Karlsruhe, Germany (or equivalent thereof), can be used to determine the Viscosity. Use a C35/1 cone & plate geometry (35 mm cone, 1 degree angle), run for 30 seconds in controlled rate mode at 250 inverse seconds shear rate. Procedural details such as zero point determination, gap setting, and filling sample volume are straightforward to one skilled in the art, and are guided by the RSI 00 software. A water bath cools the base plate to 20 degrees Celsius. Factors affecting Viscosity include the levels of film former, plasticizer, thickener, and stabilizer such as clay, the volume of pigment (organic pigments have a greater volume/mass ratio 13

than inorganic pigments and accordingly tend to increase viscosity on an equal wt/wt basis), and the types and amounts of diluents.

Wet milling can be performed using a variety of mills such as are known in the art, e.g., shear (e.g., Silverson mill), sonication, mixers, compression mills such as ball mills, paint shakers, and the like. Appropriate safety practices associated with milling of volatile or explosive materials must be observed, such as described in the examples herein. Stirred ball mills are preferred for the achievement of higher gloss, especially where the composition being wet-milled contains a clay. Without intending to be bound by theory, it is believed that stirred ball milling provides force sufficient to reduce the clay particles to submicrometer size, whereas other methods such as paint shaking tend not to provide sufficient force.

An exemplary, laboratory size stirred ball mill suitable for use herein is the MiniZeta 03 manufactured by Netzsch Inc. of Germany, employing about 300 ml of 0.6-1 mm Yttrium-Doped Zirconium beads and typically powered by an air compressor or house air supplying about 100-120 psi. The milling chamber and shaft should be cooled to avoid loss of volatiles, generally to below 20°C, prior to and during milling, e.g., using a suitable re-circulating cooling bath set to cool to between 0°C and -10°C.

The ingredients of the diluent system are preferably premixed to homogeneity before combination with the pigment to be wet-milled. Mixing can be accomplished by a variety of methods, e.g., shaking, stir-mix, shear mix, etc. The dry ingredients, including the pigments and any clay, are then added and mixed to wet out all the dry materials to ensure the dry ingredients are at least grossly dispersed in the liquid diluent. The pigment/diluent mixture is then wet-milled to reduce the particle size distribution of the pigment and to further disperse the pigment in the diluent system. Preferably, after wet-milling, at least about 80 vol% of the pigment has a Wet Particle Size of less than 1000 nm. More preferably, at least about 90 vol%> of the pigment has a Wet Particle Size of less than 1000 nm. The material is milled for a time and at a flow rate sufficient to allow the pigment to interact with the carrier to reduce aggregation of the pigment. Milling is 14

preferably done under generally closed conditions (i.e., the product is protected from significant evaporation or other losses by appropriate sealing of the mill). Typical milling times for pigment slurries and final products are from about one to two hours depending on the flow rate of the slurry/product. The flow rate is generally determined by the mill speed and product rheological properties; the mill speed is in general adjusted to provide uniform, continuous flow in the mill. With the MiniZeta, a milling speed of approximately 1400 to 1500 RPM's is preferably used. Flow rates of around 2 ml/second or faster can typically be milled for only one hour. Slower flow rates should be milled to ensure numerous passes of the materials through the mill and reduction of aggregates, e.g., for about two hours. During milling, care should be taken to ensure that there are no dead-zones that will prevent material from being milled. For example, the materials in the feed chamber may be stirred approximately every 20-30 minutes. A typical batch size using the Mini-Zeta is between about 250-600 grams. Where the composition contains mica, care is preferably taken to ensure that the particle size of the mica in the finished product will be much larger than the wavelength of light, e.g., to achieve the desirable reflection optical appearance of mica. Therefore, milling of mica is preferably avoided or minimized. Typically the mica is added at the end of the wet milling step. For example, the mica is added after milling the other pigment particles to the desired submicrometer particle size in the wet milling process. Milling is then continued for 5-10 minutes to disperse the mica.

Air-mill and wet-mill processes are further described, for example, in:

(1) "High Flow Grinding and Dispersion", Henry Way, Netzsch Incorporated company report, Netzsch Incorporated, Grinding & Dispersion Equipment

Division, 119 Pickering Way, Exton, PA, USA (July 5, 1995);

(2) "Agitator Bead Mills Affected by Energy and Quality Awareness", Diapl. Ing. G. Kolb, Netzsch Incorporated company report, Netzsch-Feinmhltechnik GmbH; 15

(3) "The Rate of The Limit Particle Size of Ultrafme Grinding of Hard Materials in Liquid", Genji Jimbo & Toyokazu Yokoyama, Department of Chemical Engineering, Nagoya University, Japan, IFPRI report (1991);

(4) "Chemical Engineering Analysis of Fine Grinding Phenomenon and Process", Genji Jimbo, Journal of Chemical Engineering of Japan, Vol. 25,

No 2. (1992);

(5) "Attrition of Particulate Solids", M. Ghadiri, J. Subero and D.G. Papdopoulos, Department of Chemical Engineering, University of Surrey, UK, IFPRI report (June 1997); (6) "An Experimental Study of Fragmentation by High Velocity Impacts on a Target", Pierre Guigon, Marie-Noelle Pons, Alain Thomas, John Dodds, IFPRI Annual Report (November 1995);

(7) "Computer Simulation of Particle Fracture", Alexander V. Potapov & Charles S. Campbell, Department of Mechanical Engineering, University of Southern California, IFPRi report ( 1997); and

(8) "Granulation Using Mechanical Agitation", P. York, A. Faure, I. M. Grimsey, The School of Pharmacy, University of Bradford, IFPRI report, (1997).

After wet-milling of particulates, the product can be combined in conventional manner with other ingredients of the nail polish composition, if necessary, to provide the polish. Optional Components

The compositions of the present invention may additionally comprise optional components such as are known in the art to enhance their performance as a nail polish. For example, antifoams, buffers, chelating agents, coalescents, dispersing agents, dyes, epoxies, fillers, other pigments, preservatives, resins, plasticizers, therapeutic and/or prophylactic agents, thickeners, wax additives, wetting agents, and the like can be included in the compositions herein. These components may be added to the compositions hereof singularly or in admixture provided they do not adversely affect the objects of the invention 16

Such optional components may be dispersed, solubilized, or otherwise mixed into the composition, either during or after wet-milling, using conventional techniques. Ingredients that will cause shear induced agglomeration, e.g., water or polyurethanes, as well as additional pigments or fillers, are preferably added after the wet milling process, typically using a paint shaker.

Non-limiting examples of optional components are given below. Plasticizers

The compositions hereof may comprise one or more plasticizers such as are known in the art. The plasticizer is generally used in an amount to plasticize the film forming polymers so that the nail polish has acceptable flexibility on the nail. The compositions preferably comprise from about 3% to about 20%, more preferably from about 5% to about 20%>, even more preferably from about 6%> to about 15%, most preferably from about 6% to about 10%, plasticizer.

Preferred plasticizer systems are those which reduce brittleness and increase toughness of the nail polish films and which do not inordinately increase viscosity of the nail polish at the level used.

Preferred plasticizers are selected from the group consisting of polar plasticizers comprising epoxy linkages, linkages comprising a nitrogen atom such as amide, imide, urea and/or urethane linkages (including polar resin plasticizers comprising such linkages), polyesters, polyester acids (e.g., di-and tri-acids), phthalates, camphor and mixtures thereof. The compositions hereof preferably comprise a plasticizer selected from the group consisting of polar plasticizers comprising amide linkages, polyesters, polyester acids, and mixtures thereof.

Nonlimiting examples of suitable plasticizers are alkyl toluene-sulfonamides, e.g., ethyl toluene-sulfonamide (e.g., Uniplex PX-45 commercially available from Unitex Chemical Corp. of Greensboro, NC): toluene sulfonamide formaldehyde ("TSF"); polyesters, e.g., Uniplex 670P (commercially available from Unitex Chemical Corp. of Greensboro, NC); polyester acids, e.g., C₃-C₂₀, preferably C₄-C_!2, more preferably C₆-C₁₀ polyester acids (including di- and tri- acids), such as polyester sebaceates (e.g., Paraplex G-25®, commercially available from C.P. Hall,

Bedford Park, IL) and polyester adipates (e.g., Paraplex G-50®, commercially 17

available from C.P. Hall); those disclosed in WO 97/00664, Chen et al, assigned to Eastman Chemical Co; phthalates, e.g., diethyl phthalate, dibutyl phthalate, and dioctyl phthalate; nonionic surfactant polymers, e.g., tartrates, (e.g., diethyl tartrate and dibutyl tartrate), phosphates (e.g., diethyl phosphate and dibutyl phosphate), and glycols (e.g., tetraethylene glycol di-2-ethylhexoate, commercially available from

C.P. Hall as Tegmer®)); camphor; sucrose acetate isobutyrate; and castor oil.

Preferred plasticizers have a number average Molecular Weight of about 10,000 or less. Preferred compositions are essentially free of, and preferably contain no formaldehyde resins. Plasticizer mixtures comprising at least one alkyl toluene-sulfonamide (e.g.,

C,-C₁₀, preferably C₂-C₄ alkyl toluene-sulfonamides) are preferred. A blend of ethyl toluene-sulfonamide and at least one other plasticizer is most preferred. Preferred compositions comprise from about 3% to about 8% (more preferably from about 4% to about 7%, most preferably from about 4%> to about 6%) alkyl toluene-sulfonamide and a total of from about 0.1% to about 6%> (more preferably from about 1% to about 5%, most preferably from about 2% to about 3%) of one or more other plasticizers. Preferred other plasticizers are polyesters, polyester acids, camphor, phthalates, and mixtures thereof.

Particularly preferred compositions comprise a plasticizer selected from the group consisting of polyesters, polyester acids, and mixtures thereof, more preferably selected from the group consisting of polyester acids. Polyester adipates are preferred polyester acids. Such plasticizers are preferably used in an amount of from 0.1% to about 6%>, more preferably from about 1% to about 5%, most preferably from about 2% to about 3%>. Preservatives

One or more preservatives such as are known in the art may be added to the present compositions to prevent, inhibit, or retard microbial growth in the composition. Preferred preservatives include benzophenone, methyl paraben, ethyl paraben, propyl paraben, benzyl alcohol, benzoic acid, benzoates, sorbates, sodium dehydroacetate, l-(3-chloroallyl)-3,5,7-triaza-l-azoniaadamantane chloride (which 18

may be obtained commercially as Quaternium-15® from Dow Chemical Co., Midland, MI. Benzophenone is preferred.

The compositions preferably comprise from 0%> to about 0.1% of preservative. Resins

One or more resins may be added to the present compositions, e.g., to promote adhesion, to strengthen the film forming polymers, and/or to increase gloss. The resins, for example, epoxy resins such as toluene-sulfonamide-epoxy, can also plasticize the composition. Examples of suitable resins include epoxies and polyacrylics, including Polytex E75® (toluene-sulfonamide-epoxy) and NX-55 (both commercially available from Estron Chemical, Inc., Calvert City, KY),

Acryloid B66® (commercially available from Rohm and Haas, Philadelphia, PA) and Avalure AC315 (commercially available from B. F. Goodrich, Cleveland, OH). Preferred compositions comprise both epoxy and polyacrylic resin. A composition preferably comprises from 0% to about 15%, more preferably from about 0.5% to about 10%,even more preferably from about 0.5% to about 6%, most preferably from about 1% to about 5%, resin by weight of the composition. Slip Aids One or more slip aids may be added, e.g., to improve surface friction, water resistance, abrasion resistance, and mechanical properties. Slip aids which may be used include wax additives including, for example, animal, fossil, vegetable, mineral, or synthetic waxes. Suitable wax additives include beeswax, carob, candelilla, ozocerite, polyethylene waxes, paraffin waxes, polypropylene waxes, polytetrafluoroethylene (commercially available as Teflon^® from DuPont, Wilmington, DE), nylons, polyamides, and materials containing silicone such as dimethicone and copolymers of polyether and polysiloxane. Any solid slip aids should be added after all milling has been completed.

The present compositions preferably comprise from 0% to about 1%, more preferably from about 0.001% to about 0.50%>, and most preferably from about 0.001%o to about 0.05%) of slip aid. 19

Therapeutic and/or Prophylactic Agents

One or more therapeutic and/or prophylactic agents, for example, vitamins, proteins, anti-fungal agents, anti-microbial agents, and sunscreens (including UV-A, UV-B, and broad spectrum solar filters) may be added to the present compositions for the further care and protection of the nails. Stabilizers

One or more stabilizers may be added to the compositions herein, e.g., to prevent pigment from settling and to achieve desired application properties.

Preferred stabilizers include clays, e.g., organically modified bentonites and hectorites such as stearalkonium bentonite and stearalkonium hectorite

(commercially available from Rheox, Inc. of Hightstown, NJ).

The present nail polish compositions preferably comprise from 0.25% to about 3%, more preferably from about 0.5% to about 2.5%, and even more preferably from about 1 % to about 2%> of stabilizer, by weight of the composition. Intermediate slurries hereof generally comprise up to about 10% stabilizer, preferably from about 3%> to about 8% stabilizer. Method of Using

A layer of nail polish may be prepared by standard application of the composition to the nail using a standard brush-applicator as is commonly utilized in the art (or equivalent thereof) and drying, that is, removing sufficient liquid diluent (through evaporation of volatiles, most preferably at ambient pressures and temperatures), to form a substantially dry layer, i.e., a layer which feels dry, smooth, and not tacky when it is touched with a human fingertip.

One or more layers of the composition may be applied to the nail. Generally from 1-4 layers, and preferably from 1-2 layers, is applied to the nail. Typically, on each application about 25 mg of the composition is applied per nail and allowed to dry to form a layer about 35 microns thick.

The compositions may be used as a clear coat (non-colored), color coat, basecoat, topcoat, or other coating on the nail. Accordingly, other nail treatment compositions such as are known in the art, including nail polishes, may be applied to the nail in addition to the compositions hereof. However, the compositions hereof 20

are suitably used as the sole nail polish composition, e.g., as a clear coat or color coat.

The compositions of the present invention may be presented to a user or potential user (hereinafter "users") of the composition in association with information which informs such users that use of the composition will provide one or more benefits, including, but not limited to, high gloss, good coverage, and/or wear properties such as resistance to chipping, peeling, scratching or denting, and the like. Such information may also include instructions for use to obtain such benefits, e.g., including the method steps described above. By "in association with information" it is meant that the information is either directly printed on the container for the composition itself (including direct printing on the container per se or indirectly via a label or the like affixed to the container), or presented in a different manner including, but not limited to, a brochure, print advertisement, electronic advertisement and/or other advertisement, so as to communicate the information to a consumer of the composition. Such information may accordingly comprise words, pictures, and the like.

Properties of the Compositions/Films & Test Methods Wet Particle Size Analysis A Horiba LA-910, laser scattering particle size distribution analyzer

(available from Horiba, Ltd, Irvine CA, USA, e.g., Windows™ Version 1.08d), or an equivalent thereof, is used to determine the Wet Particle Size of the wet milled pigments and pigments present in a nail polish composition or intermediate. The Wet Particle Size is determined for a representative sample of the product; the product should be mixed to ensure macroscopic homogeneity prior to testing. For wet pigments, the analyzer is equipped with a fraction cell holder and cell. Analysis is conducted in accordance with the operating manual. For wet products, the relative refractive index is set at 2.20 - O.li.

The product being tested is diluted with the liquid diluents in the formulation to be tested, in the ratios in the formulation to be tested, in accordance with the Horiba LA-910's ability to read the sample. Typically, about one drop of product 21

from a disposable pipette is diluted with from about 10 to 15 ml of liquid diluent. The product should be dispersed in the liquid diluent(s) with weak agitation force prior to analysis. The particle size of this mixture is then measured using the Horiba LA-910, with the fraction cell and fraction cell holder following the manufacturer's instructions.

Where the product contains mica, Wet Particle Size is determined after first centrifuging a homogeneous sample in the following manner. In a 50-mL centrifuge tube with screw on cap, place 0.75-mL product and then fill the tube to the 40 ml mark with the appropriate diluents (typically about 39-ml liquid diluent). Shake this to thoroughly mix the product with the diluent. Centrifuge this mixture for a time sufficient to sediment the mica, leaving the remaining pigment essentially in suspension in the liquid diluent. Using an International Clinical Centrifuge (Model CL) (available from International Equipment Co. of Boston, MA, USA), or equivalent thereof, centrifugation for two minutes at half the full speed (i.e., about 1675 rpm and 437.5 g-forces) will typically suffice. After centrifuging, the top of the liquid in the tube (containing suspended pigment essentially free of mica) is measured for particle size using the Horiba LA-910, with the fraction cell and fraction cell holder following the manufacturer's instructions. The particle size of the suspension is typically measured without the need for further dilution. If necessary for the Horiba LA-910's operation, liquid diluent may be added to enable testing.

The Horiba LA-910 plots the particle size versus the frequency % and the cumulative %> over the particle size. A Horiba LA-910 plot representative of the present invention is shown in Figure 1. The Horiba LA-910 also reports the mean, mode, median, span and standard deviation of particle sizes of the sample. As used herein, the Wet Particle Size refers to the mean particle size. The Horiba further reports volume % of particles having a mean particle size above certain specified sizes, e.g., above 0.1, 1, 10, 100, or 200 micrometers. The Horiba also reports the % frequency and % over particle size for numerous mean particle sizes within the sample. 22

The nail polish compositions of the invention comprise pigment particles having a Wet Particle Size of less than 1000 nm (1 micrometer), according to the above method. Especially preferred are compositions wherein the pigment has a Wet Particle Size of from about 250 nm to about 750 nm. Preferably, at least about 80 vol%>, more preferably at least about 99 vol%, of the total pigment in the composition has a Wet Particle Size of less than 1000 nm. Gloss Value

The present compositions have a Gloss Value of at least about 75, preferably from about 75 to about 97. Gloss Value is determined based on specular gloss, which represents the amount of light being reflected from the surface of the film, using conventional reflectrometry techniques. Principles of reflectrometry are described, for example, in "The Measurement of Appearance" by Richard S. Hunter, 2^nd Ed., pp. 75-89.

The Gloss Value is determined by casting the nail polish on a smooth, clear polyester sheet available from the Leneta Company, Mahwah, NJ, USA (Size: 0.18 mm X 194 mm X 260 mm; Form: P300-7C), or an equivalent. The polish is drawn down using a 3.0 mil bird-applicator-draw-down bar, across the sheet over a period of about 8-10 seconds to cover an area of about 9-10 inches long and 3 inches wide. Where the composition is water-borne, sufficient surfactant or wetting agent must be added to allow the composition to wet the polyester sheets. The wet draw down should have a consistent, even color across the draw-down area, indicating a consistent film thickness exists at all points across the draw-down. The polyester sheet is then placed on a level oven rack in a convection oven at 87° F for 24 hours. After drying, the thickness of the polyester sheet plus dried polish should be about 7.8 +/- 0.3 mils (0.0078 +/- 0.0003 inches).

Before measuring gloss, the polyester sheet is placed over a piece of black construction paper which serves as a background under the sheet during measurement. The gloss of the dried film is then measured by a calibrated BYK Gardner micro-TRI-gloss reflectometer (available from BYK-Gardner GmbH of Germany) or equivalent thereof, at an angle of 20°, at ten different spots on the film. The average of the 10 readings is determined and is the Gloss Value. 23

Coverage Factor

The compositions hereof can also be characterized by a Coverage Factor. Coverage Factor is influenced by the solids content, e.g., the pigment content, of the composition, and tends to increase with solids content. Coverage Factors may range from greater than 0 to 1.0, and are preferably from about 0.10 to about 0.90. The Coverage Factor is preferably greater than 0.4, more preferably greater than about 0.5. Coverage Factor is determined using the coated polyester sheet described above in reference to Gloss Value. The Coverage Factor is measured by placing the polyester sheet over a "black & white" Leneta card (available from Leneta Company, Mahwah, NJ, USA. (Form: 2A - Opacity). A Microflash 200D (available from Data Color International, Lawrenceville, NJ ) is used to measure the Y-value of the black and white portion of the card covered with the polyester sheet. The Coverage Factor is defined by the ratio of Y-value of the black portion over the Y- value of the white portion. The Coverage Factor by this method may range from 1.0 (for a film that provides complete coverage (complete hiding power) to essentially zero (a transparent film).

It has been surprisingly found that the compositions of the present invention provide a Gloss Value which is relatively independent of the Coverage Factor, such that nail polish films exhibiting both high coverage and gloss are provided. This is surprising since, for existing products of which the present inventors are aware, gloss tends to decrease with coverage.

Preferred nail polish compositions comprise a film forming polymer, a volatile diluent, and a pigment, the composition exhibiting a Gloss Value and a Coverage Factor, wherein the Gloss Value is greater than or equal to { 1 18.34 - [ 72.60 (Coverage Factor) ] } .

Alternatively preferred nail polish compositions comprise a film forming polymer, a volatile diluent, and a pigment, the composition exhibiting a Gloss Value and a Coverage Factor, wherein:

(a) when the Coverage Factor is from 0.17 to 0.45, the Gloss Value is greater than or equal to { 1 19.96 - [ 82.14 (Coverage Factor) ] }; or 24

(b) when the Coverage Factor is from 0.45 to 0.55, the Gloss Value is greater than or equal to { 164.00 - [ 180.0 (Coverage Factor) ] }; or

(c) when the Coverage Factor is from 0.55 to 0.90, the Gloss Value is greater than or equal to { 83.86 - [ 34.29 (Coverage Factor) ] }; or (d) when the Coverage Factor is from 0.25 to 0.75, the Gloss Value is greater than or equal to { 121 - [ 72.6 (Coverage Factor) ] }.

The present invention also tends to provide films having higher maximum strain, higher toughness (both determined using dynamic mechanical analysis methodology), faster drying kinetics, and stable equilibrium mechanical properties, relative to films from compositions comprising a greater distribution of pigments having a particle size greater than 1000 nm. Rheological properties

Preferred nail polish compositions hereof have rheological properties as defined by Yield Value and Plastic Viscosity. As will be understood by those skilled in the art, rheological properties are influenced by the level of solids and diluents present in the composition, including the level of any thickeners. For example, Plastic Viscosity tends to increase with increasing solid level, decreasing diluent level, and increasing thickener level. The Yield Value is preferably from about 0.3 Pascals ("Pa") to about 3.0 Pa, more preferably about 0.75 Pa to about 2.5 Pa. The Plastic Viscosity is preferably about 600 centipoise ("cP") or less, more preferably about 500 cP or less, even more preferably from about 200 cP to about 500 cP, most preferably from about 300 cP to about 450 cP. These rheological properties are measured using a controlled stress rheometer in a shear rate ramp. A Haake Model RSI 00 rheometer (or equivalent thereof) can be used, with a 60 mm parallel plate geometry set to operate with a 0.5 mm gap. Procedural details such as calibration, zero point determination, gap setting, and filling sample volume are straightforward to one skilled in the art, and are guided by the RSI 00 software. A water bath cools the base plate to 20 degrees Celsius. The software is programmed in controlled rate mode to ramp shear rate from 0 to 300 inverse seconds over a 2 minute time period, and collects 100 data points in that time. The data are modeled by the Casson equation, conveniently provided by the software. A linear regression 25

of the square root of stress versus the square root of shear rate obtains the slope and intercept according to the equation:

1/2

1/2 Λ

^■τM η„r J

Where:

T, = stress (measured, Pa)

γ = shear rate (measured, 1 /seconds)

1 = Yield Value (calculated by regression)

η_p = Plastic Viscosity (calculated by regression)

Examples

The following examples further describe and demonstrate embodiments within the scope of the present invention. The examples are given solely for the purpose of illustration and are not to be construed as limitations of the present invention, as many variations thereof are possible without departing from the spirit and scope of the invention.

In the examples below, all polymer component percentages are expressed in weight percent of solid polymer (based on the total composition).

The compositions of Examples 1-7 are representative of the present invention.

Ingredient Example 1 Example 2 Example 3

Solid NC !/" 15.15 15.15 15.15

Solid Sanres EX 499 2.35 2.35 2.35

Solid Epoxy E-75 1.103 1.103 1.103

Uniplex 670P 1 1 1

Uniplex PX45 5.2 5.2 5.2

Clay/bentonite/hectorite 1.2 1.2 1.2

Red #7 lake (Soft-tex) ' 0.512 0.006 0.168

Red #6 lake (Soft-tex) ' 0.448 0.091 0.08

Yellow #5 lake (Soft-tex) ' 0 0.035 0

TiO₂ lake 0.12 0.816 0 26

Red Iron Oxide (Soft-tex) ' 0.096 0.198 0

Black Iron Oxide (Soft- 0.024 0.054 0.016 tex) '

Mica Pearl (Flamenco 0 0 0.936 Velvet)

Butyl acetate 32.832 32.832 32.832

Ethyl acetate 27.36 27.36 27.36

Isopropyl alcohol 10 10 10

Camphor 1 1 1

Paraplex G-50 1.062 1.147 1.473

Dibutyl phthalate 0.543 0.458 0.133

¹ Sun Chemical, primary particle size about 20 nm to about 200 nm by conventional microscopic particle size analysis

Preparation of nail polish:

The mixtures should only be prepared under the direction of experienced operators who have been trained in safe practices for milling or otherwise mixing volatile solvents. Use only safely installed, wired, ventilated, temperature controlled and monitored equipment.

Blend all materials except the pigment and clay together at room temperature or below until homogeneous by combining in a jar or other suitable container and shaking on a paint shaker until homogeneous, about ^lA hour. An industrial paint shaker such as are commonly used to shake paint cans can be used (available from

Paul N. Gardner Company, Inc. of Pompano Beach, Florida).

Weigh an excess of pigments, excluding mica, in proper proportion and dry mix in an Osterizer food blender or equivalent about 1 minute until homogeneously mixed. Add this blended mixture to a Model 0 jet mill manufactured by Fluid Energy Aljet of Plumsteadville, PA, USA. Use compressed nitrogen as the fluid gas and set the grinding nozzles to 100 psi, the feed nozzle to 85 psi, and the vibration- feeding device to a feed rate of 30-40 on the Model-O dial. The feed rate is about 100 g per hour. Jet mill and collect the pigments. Add the correct amount of jet milled pigment blend and clay to the liquid ingredient mix and shake for ^λA hour on a paint shaker. Transfer the mixture to a high shear mixer such as a MiniZeta 03 mill (manufactured by Netzsch of Germany, employing about 300 ml of 0.6-1 mm Yttrium-Doped Zirconium beads). The mill is powered by an air compressor or house air supplying about 100-120 psi. The 27

milling chamber and shaft are cooled to below 20°C prior to and during milling, using a re-circulating cooling bath set to cool to between 0°C and -10°C. Mill until 99%> of the particles are less than 1 micron diameter, determined using a Horiba LA- 910 particle size analyzer equipped with a fraction cell holder and cell (available from Horiba, Ltd, Irvine CA, USA).

Add the mica in proportion and wet mill just until dispersed, for a period less than 10 minutes. Viscosity can be adjusted, e.g., by adding more clay (such as milled in solvents at ca. 4%-8% clay solids) (to increase viscosity), or by adding more solvent (to lower viscosity), followed by paint shaking to blend. Package in suitable storage containers, e.g., small nail polish bottles, at or below room temperature.

The above compositions are independently contiguously applied to human fingernails using a standard brush-applicator. A nail polish layer is allowed to form by drying under ambient conditions for a period of five minutes. Then a second layer is applied. The nail polish is allowed to dry for at least several minutes to form a wear-resistant film.

Ingredient Example 4 Example 5 Example 6 Example 7

Solid NC 1/4" 15.0 13.0 12.0 11.0

Solid Sanres EX519 2.0 4.0 5.5 7.0

Epoxy NX-55 1.1 1.6 3.1 1.6

Avalure AC315 3.0 2.5 1.5 3.0

Uniplex PX45 5.5 4.5 5.5 4.0

Clay/bentonite/hectorite 1.2 1.2 1.2 1.2

Red #7 solid (Soft-tex) ' 0.156 0.156 0.156 0.156

Red #34 solid (Soft-tex) ' 0.031 0.031 0.031 0.031

TiO2 solid 0.281 0.281 0.281 0.281

Red Iron Oxide solid 0.460 0.460 0.460 0.460 (Soft-tex) '

Black Iron Oxide solid 0.229 0.229 0.229 0.229 (Soft-tex) '

Butyl Acetate 29.7 30.3 30.0 29.7

Ethyl Acetate 24.8 25.2 25.0 24.8

Isopropyl Acetate 15.0 15.0 15.0 15.0

Paraplex G-50 1.5 1.5 0.0 1.5

¹ Sun Chemical, primary particle size about 20 nm to about 200 nm by microscopic particle size analysis 28

Nail polishes of Examples 4-7 are prepared in the manner described and used in the manner for Examples 1-3, except that no special processing is necessary for the inclusion of mica, which is absent in these compositions.

Claims

29WHAT IS CLAIMED IS:

1. A nail polish composition comprising a film forming polymer, a volatile diluent, and a pigment, characterized in that the composition exhibits a Gloss Value and a Coverage Factor, wherein the Gloss Value is greater than or equal to { 1 18.34 - [ 72.60 (Coverage Factor) ] }.

2. A nail polish composition comprising a film forming polymer, a volatile diluent, and a pigment, characterized in that the composition exhibits a Gloss Value and a Coverage Factor, wherein:

(a) when the Coverage Factor is from 0.17 to 0.45, the Gloss Value is greater than or equal to { 1 19.96 - [ 82.14 (Coverage Factor) ] },

(b) when the Coverage Factor is from 0.45 to 0.55, the Gloss Value is greater than or equal to { 164.00 - [ 180.0 (Coverage Factor) ] };

(c) when the Coverage Factor is from 0.55 to 0.90, the Gloss Value is greater than or equal to{ 83.86 - [ 34.29 (Coverage Factor) ] }; or

(d) when the Coverage Factor is from 0.25 to 0 75, the Gloss Value is greater than or equal to { 121 - [ 72.6 (Coverage Factor) ] }.

3. The composition of any of the preceding claims wherein at least 80 volume %, preferably 99 volume %>, of the pigment has a Wet Particle Size of less than 1000 nm.

4. A nail polish composition comprising a film forming polymer, a volatile organic solvent, and a pigment, characterized in that at least 80 volume %, preferably at least 99 volume %, of the pigment has a Wet Particle Size of less than 1000 nm. 30

The composition of any of the preceding claims wherein the pigment is derived from a pigment having a microscopic primary particle size of from 20 nm to 200 nm

A method of preparing a pigmented composition suitable for use in or as a nail polish comprising a pigment and a diluent, characterized in that the method comprises the steps of

(a) providing an agglomerated powdered pigment having a microscopic primary particle size of from 20 nm to 200 nm,

(b) air milling the agglomerated pigment to reduce the particle size and to fracture at least a portion of the primary pigment particles,

(c) combining the pigment from step (b) with a non-shear inducing, liquid diluent, and

(d) dispersing the pigment in the diluent such that at least 80 volume % of the resulting pigment has a Wet Particle Size of less than 1000 nm

The method of claim 6 wherein step (b) of air milling comprises using a jet- mill and step (d) of dispersing comprises using a ball mill

The method of claim 6 or 7 wherein the mixture of pigment and diluent prior to step (d) has a Viscosity of 2500 centipoise or less at a 250 inverse seconds shear rate

The method of any of claims 6-8 wherein the composition comprises two or more pigments, at least one of which is the agglomerated pigment, and the method further comprises a step of mixing the pigments before step (b) of air milling

A nail polish comprising the pigmented composition prepared according to any of claims 6-9