Wear resistant cosmetic compositions

There is provided a cosmetic composition, preferably in the form of a lip gloss composition, that is smooth, glossy, and wear resistant. The composition has an oil or liquid ester and a gel, and optionally, one or more waxes, one or more pigments, and one or more emollients.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention relates generally to cosmetic compositions. More
 particularly, the present invention relates to cosmetic compositions that
 are applied to the skin and lips, which offer enhanced ease of application
 and wear resistance, e.g. non-feathering and non-bleeding. In addition,
 the present invention provides cosmetic compositions that have features of
 traditional gloss products, namely high shine, even coverage, and light
 feel.
 2. Description of the Prior Art
 Traditional lipsticks are made of an oil or fatty base that is stiffened to
 a desired consistency with waxes of various types. The waxes serve to
 raise the melting point and improve the physical stability of the base.
 The color of the lipstick is ordinarily provided by insoluble pigments or
 lakes, which are finely dispersed in the base. In addition, a fluorescein
 dye derivative, such as tetrabromofluorescein, which stains the lips, may
 be incorporated into the base.
 A lip gloss composition is a composition used for cosmetic and lip care
 purposes and specifically for lip coloring, in much the same manner as
 lipsticks are used. A lip gloss composition has a very high shine.
 Moreover, the lip gloss composition is commonly semi-solid, and has a
 fluid, smooth consistency. These characteristics are preferred by
 consumers in many situations.
 However, lip gloss compositions are moved too readily on the surface of the
 lips. Such movement results in very low wear resistance. For example, lip
 glosses will accumulate in the fine creases in the skin of the lips and
 the skin immediately surrounding the lips. This tendency is called
 feathering, and is undesirable to consumers. Additionally, the oils
 contained in a lip gloss oftentimes cause the color to migrate beyond the
 outer perimeter of the lips, resulting in a halo effect. This tendency is
 called bleeding, and is undesirable to consumers.
 Prior art examples of wear-resistant cosmetic compositions include U.S.
 Pat. No. 4,699,780 to Jennings, et al., titled Cosmetic Composition. The
 Jennings et al. patent provides for a composition comprising a resin, a
 polysiloxane, a polyolefin that is liquid at room temperature, and at
 least one hardening agent.
 However, there is an ongoing need for cosmetic compositions, which may be
 used, for example, as lip gloss compositions, that combine high shine,
 fluidity, and smooth consistency with wear resistance and vibrant color.
 SUMMARY OF THE INVENTION
 It is an object of the present invention to provide a cosmetic composition,
 such as a lip gloss composition, that provides high gloss, fluidity,
 smooth consistency, long-lasting shine, and long-lasting color.
 It is another object of the present invention to provide such a cosmetic
 composition that provides vibrant lip gloss colors combined with
 resistance to feathering and bleeding.
 Accordingly, there is provided a cosmetic composition, preferably in the
 form of a lip gloss composition, that is semi-solid, glossy, long-lasting
 and wear resistant. The composition comprises a gel base, and optionally,
 one or more waxes, one or more colorants, and one or more emollients.
 DETAILED DESCRIPTION OF THE INVENTION
 The present invention provides a cosmetic composition, preferably a lip
 gloss composition, that is smooth, glossy, wear resistant and stable.
 The cosmetic composition according to the present invention preferably
 comprises a gel base that is present in an amount about 75.0 percent to
 about 99.0 percent by weight (wt %) of the total weight of the
 composition. More preferably, the base is present in an amount about 80 wt
 % to about 90 wt % and, most preferably, about 80 wt %. Moreover, the
 cosmetic composition optionally comprises up to about 5.0 wt % of one or
 more waxes, up to about 15.0 wt % of one or more colorants, such as
 pigments, and up to about 20.0 wt % of one or more emollients.
 The gel base includes a liquid ester or an oil, preferably non-polar, which
 can be either natural or synthetic, and a gellant. More preferably the oil
 or ester of the base is a non-polar, branched chain aliphatic hydrocarbon
 homopolymer and, most preferably, hydrogenated polyisobutene. Hydrogenated
 polyisobutene conforms generally to the formula:
 ##STR1##
 wherein x is an integer greater than 1.
 The hydrogenated polyisobutene imparts emolliency, flexibility, and high
 gloss to the cosmetic composition.
 The hydrogenated polyisobutene is preferably about 60 wt % to about 99 wt %
 of the gel base.
 In addition, the gel base also includes one or more gellants in an amount
 about 1.0 wt % to about 40 wt % of the total weight of the gel base. More
 preferably, the total amount of gellant is present in an amount about 1 wt
 % to about 20 wt % of the total weight of the gel base and, most
 preferably, about 10 wt %.
 The gellant(s) are preferably one or more block copolymers. These
 copolymers are set out in more detail in U.S. Pat. No. 5,221,534, which is
 incorporated herein by reference. A preferred hydrogenated mixed-block
 copolymer consists of (1) styrene (2-cyclohexa-3-diene); (2) ethylene; and
 (3) propylene or butylene monomers; or the derivatives thereof, having the
 general structures:
 ##STR2##
 ##STR3##
 where R.sub.1 to R.sub.8 are each independently a hydrogen or a hydrophobic
 alkyl chain.
 This hydrogenated mixed-block copolymer is known as, for example, a
 hydrogenated styrene/ethylene/propylene tri-block copolymer or a
 styrene/ethylene/butylene tri-block copolymer. The "blocks" of polymerized
 styrene monomers are mixed with "blocks" of polymerized ethylene and
 propylene or butylene monomers. Typically, this hydrogenated mixed-block
 copolymer acts as a film former, as well as a gellant, plasticizer,
 emollient and/or moisturizer. The gellants promote improved skin
 occlusivity and transepidermal water loss (TEWL). Clinical studies with
 gelled mineral oil have shown that moisturization as measured by TEWL
 improves 53% even though the gel base contains more than 90% mineral oil.
 It should be understood that one or more hydrogenated
 styrene/ethylene/propylene mixed-block block copolymers and/or
 styrene/ethylene/butylene mixed-block copolymers might be used in the
 present compositions.
 A preferred hydrogenated block copolymer for use in the present invention
 is available from Penreco Technology Group, Karns City, Pa., and results
 in a clear gel base.
 Since the cosmetic compositions, such as lip glosses, have a fluid and
 smooth consistency, the viscosity of the gel base should be about 50,000
 centipoise (cps) to about 160,000 cps at 25.degree. C. when tested with a
 Spindle T-C at 5 rotations or revolutions per minute (rpm) and the color,
 based on ASTM D1500, should preferably have a value less than 0.5.
 The present invention also comprises an antioxidant in an amount up to
 about 0.5 wt % of the total weight of the composition. More preferably,
 the antioxidant is present in an amount up to about 0.4 wt % of the total
 weight of the composition.
 The antioxidant is preferably selected from the group consisting of:
 ascorbyl palmitate, butylated hydroxytoluene (BHT), butylated
 hydroxyanisole (BHA), tocopheryl acetate, and ascorbic acid. More
 preferably, the antioxidant is BHT.
 BHT is a substituted toluene that conforms to the formula:
 ##STR4##
 A cosmetic composition according to the present invention may be made
 without any wax. However, if waxes are included in the present
 composition, the amount of wax should be minimized to maintain the clarity
 of the composition. By maintaining a clear and transparent composition,
 ingredients for providing visual effects (e.g., glitter) may be
 incorporated into the composition. Similarly, a clear and colored
 composition will provide truer color to the composition. Accordingly, it
 is preferred that the amount of wax is only up to about 5 wt % of the
 total weight of the composition. More preferably, one or more waxes will
 be present in an amount about 1 wt % to about 3 wt % of the total weight
 of the composition to maintain such clarity. However, more wax can be used
 if clarity is not a concern.
 The one or more waxes can be natural or synthetic waxes. Preferably, one or
 more microcrystalline waxes are used in the present invention. These
 microcrystalline waxes preferably have C.sub.8 to C.sub.50 hydrocarbons
 and a melting point preferably greater than about 60.degree. C. (about
 51.degree. F.). Other waxes that can be used in the present invention are
 candelilla, carnauba, ozokerite, paraffin, polyethylene, beeswax, ceresin,
 hydrogenated castor oil, japan wax, or mixtures thereof.
 Further, a cosmetic composition of the present invention may include
 colorants and emollients.
 In a preferred embodiment, the cosmetic composition may include up to about
 15.0 wt % of one or more colorants. More preferably, the colorants will be
 present in an amount about 8 wt % to about 12 wt % and, most preferably,
 about 10 wt % of the total weight of the cosmetic composition. Such
 colorants include pearls and pigments that are known in the art. For
 example, pigments used in the present invention may be metal oxide
 pigments, such as iron oxides and titanium oxides, FD&C dyes, D&C dyes,
 and lakes.
 A cosmetic composition according to the present invention may also contain
 one or more emollients other than the ingredients in the gel base in an
 amount up to about 20.0 wt % of the total weight of the cosmetic
 composition. More preferably, emollients will be present in an amount
 about 2 wt % to about 15 wt % of the total weight of the cosmetic
 composition and, most preferably, about 5 wt %. Emollients useful in the
 present invention include any known to the art, including, but not limited
 to, oils and esters, such as lanolin and petrolatum.
 In addition, a cosmetic composition according to the present invention may
 comprise other ingredients and additives known in the art, depending on
 the purpose for which the formulation is intended. For example, a lip
 gloss according to the present invention may optionally include one or
 more vitamins, sunscreens, fillers and fragrances.

The following is an example of a cosmetic composition according to the
 present invention.
 EXAMPLE 1
 Lip Gloss

Ingredient Wt %
 Hydrogenated polyisobutene/ 80
 hydrogenated styrene-ethylene-propylene
 copolymer/BHT
 Film Former 4
 Wax 3
 Colorants 10
 Preservative 0.1
 Fragrance 0.3
 Emollients q.s.
 This formula provides superior resistance to feathering and bleeding, as
 well as long-lasting shine and color, as a direct result of the thickening
 property achieved through the gel base. This thickening property also
 serves to drastically reduce the settling rate of the dispersed pigment
 particles by physically restraining the movement of the particles. In
 addition, the polymer system, itself, can confer an additional element of
 stabilization to the composition further enhancing the overall stability
 of the composition.
 The present invention having been described with particular reference to
 the preferred forms thereof, it will be obvious that various changes and
 modifications may be made herein without departing from the spirit and
 scope of the invention as defined in the appended claims.