Abstract:
A nail cleansing composition useful for removing stains from human nails, nail stain removing kits, and a method for removing stains from nails using the composition of the invention.

Description:
TECHNICAL FIELD 
     A nail cleanser for human nails which removes various types of stains. 
     BACKGROUND OF THE INVENTION 
     The human nail is very porous and becomes more so with age. This porosity increases the tendency of nails to stain. Staining may be caused by the repeated use of nail lacquer over a prolonged period of time, nicotine from handling lighted cigarettes, or from various chemicals to which people may be exposed in their homes or occupations. Nails also yellow with age due to melamine, a brown pigment synthesized in the body by normal biological processes and carried up into the nails from the nail beds. The stains due to nail lacquers are believed to be caused by bleeding of pigmentary materials such as partially solubilized dyes into the nail. In addition, the nitrocellulose found in the nail lacquers is known to heavily contribute to nail staining. The esthetically displeasing result of stained nails has lead to different nail stain removers. 
     Many of the standard preparations use bleaches which are extremely drying and irritating to nails. Preparations containing strong alkali such as sodium hydroxide or alkali metal hydroxides are also known. For obvious reasons these preparations are not desirable. 
     In U.S. Pat. No. 4,344,932 a nail cleanser comprised of chelating agents such as EDTA and urea in a liquid carrier is disclosed. The chelating agents remove stains by complexing with the metal ions which are present in many nail stains. However some stains, such as residual dyestuffs left on nails due to lacquers, do not respond as effectively to chelating agents alone, thus resulting in a less effective cleanser. Further, urea is often irritating to tissues surrounding the nail so it is desirable to find nail cleansing preparations which avoid these drawbacks. 
     SUMMARY OF THE INVENTION 
     The invention is directed to a composition useful for removing stains from human nails comprising the following essential constituents in a cosmetically suitable vehicle: 
     a) an abrasive agent, and 
     b) one or more white pigments. 
     The invention is also directed to a nail stain removing kit comprised of single units of porous material containing the dehydrated composition set forth above, which unit is moistened with water immediately prior to use to yield a nail cleansing pad which is used to scrub the nails. 
     The invention is also directed to a nail stain removing kit comprised of a container filled with the composition of the invention. 
     The invention is also directed to a method for removing stains from human nails comprising cleansing nails with the composition set forth above. 
    
    
     DETAILED DESCRIPTION 
     The composition essentially contains an abrasive agent. Suitable abrasive agents include pumice, polyethylene granules, aluminum oxide, silica, magnesium aluminum silicate, kaolin, finely ground nut shells or diatomaceous earth. About 1-25% of abrasive agent is a suitable range. The preferred abrasive agent is pumice or magnesium aluminum silicate. 
     The composition also essentially contains one or more white pigments. The pigment functions by cosmetically obliterating surface nail stains. Pigments such as zinc oxide, titanium dioxide, barium sulfate, zinc sulfide are suitable, although titanium dioxide is preferred. A suitable range of white pigment is about 1-20%. The abrasive agent will polish nails by mechanical abrasion, while the stain residues are visually mitigated by the white residue left by the white pigment. The composition may additionally contain a variety of metallic salts such as aluminum chloride or aluminum chlorohydrate which react with residual dyestuffs on nails, as well as absorbents (e.g. talc, blanc fixe) and/or chelating agents (e.g. EDTA). 
     The essential constituents of the invention are contained in a cosmetically suitable vehicle such as an oil in water emulsion, water, an anhydrous carrier or an aqueous composition comprised of water and a carbopol type gel. Anhydrous vehicles are such as oils gelled with bentonite clays or oils gelled with silica. Water may be used alone or combined with a Carbopol™ type gel such as carbomer 910, carbomer 934P, carbomer 940, carbomer 941, which are either a polymer of acrylic acid crosslinked with an allyl ether of pentaerythritor or sucrose, magnesium aluminum silicate, PVP hydrogels. The former is the preferred vehicle. 
     The composition may additionally contain one or more of a solvent, solubilizer, protectant, pigment, metallic salt, humectant vitamin, conditioner emollients, humectants, thickeners, texturizers, solubilizing agents, preservatives, pigments, protectors, vitamins, conditioners, colorants, metallic salts, satabilizers or colorant. 
     The suitable solvents may be C 1-6  organic alcohols such as isopropanol, methanol, ethanol, isopropanol, N-methyl pyrrolidone, butyrolactone; or ethers, for example polyethylene glycol (PEG)-20 methyl glucose ether. 
     Solubilizers may be added to increase the solubility and consistency of the ingredients and may be selected from the glycols such as propylene glycol, butylene glycol, etc. 
     Various protectants may be added. The suitable protectants are well known to those skilled in the art. They may be such as polyvinyl pyrrolidone, allantoin, bisabolol, herbal and vegetal extracts, various humectants, including propylene glycol, hexylene glycol, glyceral, alkyl glucosides, alkoxylated alkyl glucosides, sorbitol, salts of hyaluronic acid, salts of pyrrolidone carboxylic acid, etc. 
     Various vitamins may be added for nutrient effects and include Calcium Pantothenate which is vitamin B 6  Salt. 
     The acceptable colorants are those generally known to be suitable in cosmetics such as the FD&amp;C and D&amp;C colors such as Blue #1, Yellow #5, Red #4 etc. Various preservatives may be added, including phenoxyethanol, alkyl esters of p-hydroxybenzoic acid, imidazolidinyl urea, quaternium-15, etc. 
     Conditioners may also be added to impart therapeutic properties. Alkoxylated lanolins, alkyl glucosides, cationic surfactants, amphoteric surfactants, solubilized vegetal extracts, proteins and derivatives thereof, etc. 
     The composition of the invention is best marketed in a kit or single container so that the consumer may purchase a specified amount to be used over a certain period of time. 
     A suitable nail stain removing kit is comprised of single units of porous material containing the dehydrated composition of the invention. The single unit is a small sponge preferably with abrasive properties. Abrasive polyester pads are excellent since they have a degree of abrasiveness to them. The pad is impregnated with the wet composition of the invention and then allowed to dry. A number of dehydrated pads maybe packed into a kit or suitable package form for sale to the consumer. The user merely moistens the pad with water and uses it to scrub the nails. 
     The composition may be also sold in a suitable container. For example, a small squeezable plastic tube is also an excellent vehicle. The tube may be filled with a small amount of the composition in a paste form. The tube is then purchased and used by the consumer. 
     Also, the composition may be sold in a container similar to a mascara tube which container contains a sponge or brush type applicator. The lid of the container, to which the applicator is attached is immersed into the composition when the cap is placed onto the tube. Upon removal of the cap from the tube, the attached applicator, containing the composition of the invention, may be applied directly to the nails and the applicator used as a scrubbing or cleansing vehicle. 
     The instant invention will be illustrated in accordance with the following examples which are set forth for the purposes of illustration only. 
     EXAMPLE 1 
     Nail Stain Remover #1 
     The following ingredients were combined in the following proportions to yield a slurry composition. 
     
         ______________________________________          W/W %Water Phase      Pref&#39;d. Amt. Pref&#39;d. Range______________________________________Water, deionized 58.399       50-75Pumice, 2F Grade 5.00          1-25Pumice, 4F Grade 10.00         1-25Propylene Glycol 10.00         1-15PEG-20 Methyl glucose ether            10.00         1-15Titanium Dioxide 5.00          1-15FD&amp;C Blue #1     0.001        0.0001-0.005Triethanolamine  0.50         0.10-2.50Phenoxy ethanol  0.75         0.10-1.00Methyl paraben   0.10         0.10-1.00Carbomer 940     0.25         0.10-1.00______________________________________ 
    
     EXAMPLE 2 
     Nail Stain Remover #2 
     The following ingredients were combined in the following proportions to yield a slurry composition 
     
         ______________________________________           W/W %Water Phase      Pref&#39;d. Amt. Pref&#39;d. Range______________________________________Water            67.27        40-70Carbomer 940     0.75         0.1-1.5Propylene Glycol 10.00        5-15PEG-20 Methyl Glucose Ether            10.00        5-15Kaolin           5.00         1-20Titanium Dioxide 1.00         1-10Triethanolamine  0.98         0.5-1.5Pumice 2F Grade  5.00         1-10______________________________________ 
    
     EXAMPLE 3 
     Nail Stain Remover #3 
     The following ingredients were combined in the following proportions to yield a slurry 
     
         ______________________________________           W/W %Water Phase      Pref&#39;d. Amt. Pref&#39;d. Range______________________________________Water            65.00        60-70Magnesium Aluminum Silicate            2.00         1-10Trisodium EDTA   5.00         1-10Talc             2.00         1-3PVP              0.50         0.5-2.00Zinc oxide       4.00         1-10______________________________________