COMPOSITION FOR SEMI-PERMANENT SKIN COLORATION Field of the Invention This invention is directed to a composition and a method for safe, semi- permanent skin coloration. The composition comprises a bioabsorbable material and a biocompatible, bioabsorbable coloring agent. Additionally provided is a kit of parts comprising a bioabsorbable material and a biocompatible bioabsorbable coloring agent.

Background The following references are cited herein: 1. U. S. Patent 5,836,998; 2. U. S. Patent 4,914,988; 3. U. S. Patent 5,290,273; 4. U. S. Patent 5,833,649; and 5. U. S. Patent 5,401,242.

All of the above references are herein incorporated by reference in their entirety.

There are two primary ways to apply color to mammalian skin: temporary and permanent. Temporary skin coloration agents include cosmetics, such as eyeliners, lipstick, colored powders and colored creams or lotions. Once applied, these products are easily removed with common cleansing agents such as soap and water. Temporary skin coloration requires daily application and can be difficult to consistently apply in an artistic and pleasing manner, particularly for those with sight limitations.

Another type of temporary skin coloration is painting the skin with a skin dye such as henna paste. Mehndi is a centuries-old art form in which henna based epidermal dye is applied to stain the skin in decorative patterns. It is used primarily in Middle Eastern and Asian cultures before a celebrations such as a wedding festival. Intricate designs are applied to the palms and soles of the feet.

The henna paste is applied to the skin and allowed to dry, thereby staining the epidermal layer of the skin. The epidermis eventually sloughs off, taking the dye with it. A method for applying a decorative henna stain to the skin is described in U. S. Patent 5,836,998.

Permanent skin coloration, such as a tattoo, is typically applied one time and lasts for a lifetime. Tattoo dye is injected with a needle into the dermal layer of the skin resulting in permanent coloration. The application of a tattoo can be painful and very difficult to reverse. In spite of this, it is estimated that up to 10% of the United States population currently has a tattoo.

The art of tattooing goes back many centuries. Recently, tattoos have been used as a permanent cosmetic. Once such use of a tattoo as a cosmetic is as eyeliner, as described in U. S. Patent 4,914,988, or as a lip liner.

Recently, methods have been developed to attempt to remove or lighten tattoos. For example, the use of lasers to remove a tattoo has been described in U. S. Patent 5,290,273. Covering a tattoo with another tattoo has been described in U. S. Patent 5,833,649.

Other problems associated with tattooing the skin include contamination of needles and dyes, problems with the accuracy of application of the tattoo due to tattoo machine vibration, variability in consistency of dye application between

tattoo needles, and the depth to which the tattoo needle punctures the skin. As noted, once the tattoo dye is applied to the skin, it is a permanent coloration, and errors in the application of the tattoo are difficult to reverse.

Accordingly, in light of the problems associated with temporary and permanent skin coloration, a need exists for a composition which imparts skin coloration in a safe, semi-permanent manner.

Summarv of The Invention This invention is drawn to a composition and method for semi-permanent skin coloration.

Accordingly, one aspect of this invention is a composition comprising a bioabsorbable material and a biocompatible, bioabsorbable coloring agent.

Preferably, the bioabsorbable material is selected from the group consisting of collagen, gelatin and other bioabsorbable materials, and the biocompatible, bioabsorbable coloring agent is selected from the group consisting of henna, indigo and other biocompatible, bioabsorbable coloring agents.

Another aspect of this invention is a method for applying a semi-permanent skin coloration to a mammal comprising applying to mammalian skin a sufficient amount of a composition comprising a bioabsorbable material and a biocompatible, bioabsorbable coloring agent to color the mammalian skin. Preferably, the bioabsorbable material is selected from the group consisting of collagen, gelatin and other bioabsorbable materials, and the biocompatible, bioabsorbable coloring agent is selected from the group consisting of henna, indigo and other biocompatible, bioabsorbable coloring agents.

Yet another aspect of this invention is a kit of parts comprising a bioabsorbable material and a biocompatible, bioabsorbable coloring agent.

Preferably, the bioabsorbable material is selected from the group consisting of collagen, gelatin and other bioabsorbable materials, and the biocompatible, bioabsorbable coloring agent is selected from the group consisting of henna, indigo and other biocompatible, bioabsorbable coloring agents.

Detailed Description of The Invention This invention is related to compositions comprising a bioabsorbable material and a biocompatible, bioabsorbable coloring agent which are useful for semi-permanent skin coloration. Prior to discussing the invention in further detail, the following terms are defined: The term"bioabsorbable material"refers to a compound which, when applied to the dermal layer of the skin, will eventually degrade or absorb into the body. These materials include, but are not limited to, collagen, gelatin and other bioabsorbable materials. Preferably, the bioabsorbable material is collagen. The bioabsorbable material may be degraded or absorbed into the body from about 1 day to about 4 years following application in the dermal layer of the skin. More preferably, the material is degraded or absorbed from about 1 month to about 3 years following application in the dermal layer of the skin, and even more preferably, the material is degraded or absorbed from about 6 months to about 2 years following application in the dermal layer of the skin.

The term"biocompatible, bioabsorbable dye"or"biocompatible, bioabsorbable coloring agent"refers to coloring agents, which, when applied to the dermal layer of the skin, will eventually degrade or absorb into the body.

Additionally, the coloring agent is biocompatible in that it is non-toxic when

applied to animals. Coloring agents include, but are not limited to henna, indigo and other biocompatible, bioabsorbable dyes and coloring agents. It is understood that the dyes or coloring agents are compatible with the bioabsorbable material described above. In other words, the dye or coloring agent is miscible or dispersible in the bioabsorbable material. It is understood that the dye or coloring agent is not a permanent skin dye, such as a permanent tattoo dye. Additionally, the biocompatible, bioabsorbable dye or coloring agent may be incorporated into a timed-release formulation. In other words, the dye or coloring agent may be encapsulated in small beads wherein the beads are designed to dissolve or degrade in the dermal layer of the skin after a predetermined amount of time.

The term"semi-permanent skin coloration"means that the composition of this invention imparts color to skin for a period of time after which the coloration fades away. For example, the skin coloration can last from about 1 day to about 4 years. Preferably, the skin coloration lasts from about 1 month to about 3 years, and more preferably the skin coloration lasts from about 6 months to about 2 years.

The term"mammals"refers to humans, pigs, cows, horses, sheep, goats and other mammals.

Composition The composition of this invention comprises a bioabsorbable material and a biocompatible, bioabsorbable coloring agent. The composition is useful for semi- permanently imparting color to mammalian skin.

The bioabsorbable material is selected according to the desired length of time the skin is to be colored. For example, the bioabsorbable material of the

composition may be formulated to exhibit controllable biodegradation or bioabsorbable properties. Preferred bioabsorbable materials are collagen and gelatin.

The biocompatible, bioabsorbable coloring agent is selected according to the color desired. It is understood that more than one type of dye or coloring agent may be mixed with the bioabsorbable material to obtain a desired color.

Preferred biocompatible, bioabsorbable dyes or coloring agents are henna and indigo.

It is contemplated that the bioabsorbable, biocompatible coloring agent may be incorporated into a timed-release formulation, such as incorporated into small beads which dissolve or degrade within the dermal layer of the skin after a predetermined amount of time. Accordingly, it is also contemplated that the composition comprises a bioabsorbable material and a bioabsorbable, biocompatible coloring agent, wherein the bioabsorbable, biocompatible coloring agent is prepared in a timed-release formulation.

The composition may contain additional optional additives which are compatible and/or miscible with the composition and which are non-toxic when applied to the dermal layer of skin. For example, in the case of collagen, an additive which cross-links the collagen may be added to the composition.

In general, the composition will gradually be absorbed into the body once it has been applied to the dermal layer of the skin. As the composition is absorbed into the body, the coloration imparted to the skin fades and eventually disappears.

The intensity of the color and the length of time that the coloration is present on

the skin varies with the amount of the composition that is applied to the dermal layer and with the particular coloring agent that is used.

Methods Another embodiment of this invention is a method for applying semi- permanent skin coloration to mammalian skin. The composition comprising a bioabsorbable material and a biocompatible, bioabsorbable coloring agent is applied to the dermal layer of the skin in a sufficient amount to impart coloration to the skin. The composition may be applied to the dermal layer of the skin as a cosmetic, such as eyeliner or lip liner, or may be applied as a design. In the case of livestock, such as pigs, the composition may be applied in the form of a brand or a number used to identify the livestock.

The method of this invention may utilize standard tattoo machines and needles known in the art to apply a sufficient amount of the composition to the dermal layer of the skin to impart color to the skin. Customary tattooing methods are described in U. S. Patent 5,401,242. Alternatively, the method of this invention may utilize standard collagen application techniques known in the art to apply the composition to the dermal layer of the skin thereby imparting color to the skin. In general, the amount of time required to apply the composition will depend upon the location on the skin as well as the size of the design applied to the skin. The method may also utilize standard livestock tattooing methods known in the art.

Kit of Parts A further embodiment of this invention is a kit of parts comprising a bioabsorbable material and a biocompatible, bioabsorbable coloring agent stored in separate containers. At the appropriate time, the bioabsorbable material and the

biocompatible, bioabsorbable coloring agent are mixed together to form the composition described above. The containers may be individual containers or may be a single container having a barrier separating the container into separate compartments.

EXAMPLE A composition comprising collagen and henna is prepared for injection into the dermal layer of human skin. The composition is prepared so that it may be used in a standard tattoo machine.

Using a standard tattoo application procedure, the composition is applied to the dermal layer of the skin in a subject desiring a semi-permanent tattoo.

From the foregoing description, various modifications and changes in the composition and method will occur to those skilled in the art. All such modifications coming within the scope of the claims are intended to be included therein.