Antiperspirants are used by a majority of consumers across both sexes, and are an active area for patent filing.
The following four patents include compositions and methods for stick-type, roll-on and spray formats, and a natural ingredient based deodorant.
1. Antiperspirant compositions
US Patent 10,052,271
Application No 15/915,130
Granted 21 August 2018
Assignee Procter & Gamble
It is suggested that solids and soft solids are two of the more popular forms of antiperspirants.
However, structurants like waxes tend to interfere with the release of the active and thus negatively impact the efficacy of the product.
The patent describes a solid stick antiperspirant composition that includes aluminium zirconium tetrachlorohydrex glycine, an anhydrous liquid carrier, one or more structurants and a non-ionic ethoxylated linear alcohol that is claimed to overcome this problem.
The effectiveness of an antiperspirant is related to the transport of sweat in and out of the product film to solubilise the active and transport it back into the sweat duct to form a plug; it was thought that to improve the release of the active a surfactant could be incorporated into the composition.
It was found that in a single batch process where all the ingredients are combined and mixed together at the melting point of the waxes, the surfactant has time to bind to the active, which impedes its release.
However, if the surfactant is in a hot phase with the structurant and the antiperspirant is in a cold phase, when mixed together the product rapidly starts to crystallise, which inhibits the surfactant from binding to the active.
In the preferred composition the hot phase comprises about 13% stearyl alcohol with 1% ozokerite, 2% tribehenin and 3% hydrogenated castor oil as the structurants.
The preferred surfactant is C20-40 pareth-10 at 2% with PPG-14 butyl ether at 6.50%.
The cold phase is about 25% aluminium zirconium tetrachlorohydrex glycine; the anhydrous liquid carrier is about 6% C12-15 alkyl benzoate; and other ingredients may be incorporated to further improve aesthetic and sensorial properties. The balance is dimethicone 200cs to 100% by weight.
2. Highly active antiperspirant with improved skin tolerability
US Patent 9,981,149
Application No 15/614,845
Granted 29 May 2018
Assignee Henkel
The applicants claimed that the hygiene routine of many users includes regular shaving of the underarm area before applying an antiperspirant or deodorant, but application of an ethanol-based agent to freshly shaved skin can cause a great deal of burning.
With regular use, such agents dry the skin and make it more sensitive and easily irritated. An object of the patent application was to supply water-based antiperspirant compositions that have a high antiperspirant efficacy with the greatest possible skin tolerability.
It was found that this could be achieved by adding selected amounts of L-valine to an aqueous solution of an aluminium-zirconium-glycine complex.
The patent describes antiperspirant compositions that are suitable for application with a roller applicator and contain water, aluminiumzirconium- glycine complex, L-valine and an oleogel.
The latter comprises a silicone elastomer, copolymer, hydrocarbon oil and polymethylsilsesquioxane, which is a powder that swells in oil and thickens the mixture to form an oleogel.
The oleogel greatly improves the drying of an aqueous composition. The antiperspirants are formulated as oil-in-water emulsions and a suitable non-ionic emulsifier system is steareth-2 with steareth-21 and PPG-15 stearyl ether. They have a high antiperspirant efficacy and are well tolerated on the skin.
Preferably, the aluminiumzirconium- glycine complex is present at about 12% to about 14% and the L-valine is about 0.1-0.2%. Up to 3% ethanol is included with up to 10% cosmetic oils.
Other ingredients may be incorporated to further improve aesthetic and sensorial properties, and the balance is water.
3. Aerosol antiperspirants
US Patent 9,408,799
Application No 14/779,952
Granted 9 August 2016
Assignee Colgate-Palmolive
Antiperspirants can be delivered topically in liquid form as an aerosol.
When these compositions are applied to the axillary region, the aerosol spray is deposited as fine droplets but some of the droplets may not be deposited to form an effective antiperspirant layer, thus reducing the product efficacy.
The patent describes an aerosol antiperspirant composition comprising at least one active antiperspirant ingredient, a bis-vinyl dimethicone/dimethicone copolymer, a silicone solvent, at least one fatty acid ester and at least one propellant.
It claims to provide enhanced deposition on the skin and improved antiperspirant efficacy.
Preferably the bis-vinyl dimethicone/dimethicone copolymer is present at 0.15-0.3%.
The silicone solvent is dimethicone, present at 0.9-1.2% and the preferred fatty acid ester is a mixture of isopropyl myristate and isopropyl palmitate totalling 3-4.5%; 0.25-0.35% of trialkylaryl ammonium hectorite clay is added as a thickener.
The active antiperspirant ingredient is selected from aluminium salts, zirconium salts and zinc salts.
The patent also includes a method of manufacture by combining the bis-vinyl dimethicone/dimethicone copolymer, the silicone solvent, and the fatty acid esters as a premixed gel and mixing this with the active antiperspirant ingredient.
Optionally the composition may also contain 0.5-0.75% hydrogenated soybean oil and 0.5-2% C12-C15 alkyl benzoate.
It is claimed that this composition delivers the same level of efficacy if the active level is at 10% compared with 17% from alternative compositions.
Additional components optionally include a fragrance, a preservative, an emulsifier, an antioxidant and an emollient, and at least one propellant, typically a liquefied hydrocarbon mixture of butane, propane and isobutane.
The propellant represents about 85% by weight of the total composition and all percentages shown are based on the total composition including the propellant.
4. Roll-on natural deodorant and method of use
US Patent 9,949,920
Application No 15/159,482
Granted 24 April 2018
Assignee Hakim, Noha N
The inventor suggests that many antiperspirants contain aluminium, but that has been implicated as a risk factor for both breast cancer and Alzheimer's disease.
He further claims that most skin care products use synthetic preservatives such as parabens and triclosan, which may be considered toxic in high doses and cause skin irritation and allergies, and that skin care products with lecithin and gluten may cause allergic reactions.
Described is a natural deodorant comprising about 55-65% aloe vera juice, about 10-16% coconut oil, about 4-8% Dead Sea salt, about 4-8% olive oil, about 3-7% sweet almond oil, about 3-5% emulsified wax, about 1-3% potato starch, about 0.5-1.5% apple cider vinegar and about 0.5-1.5% pure essential oils including sage, eucalyptus and tea tree.
It also contains a preservative system comprising 1.2% of a leuconostoc/radish root ferment filtrate and about 0.8% phenoxyethanol.
It is fragranced with anise, lemongrass, peppermint, tangerine, bergamot, lavender and palmarosa essential oils.
It is claimed that this natural deodorant is a combination of the Earth's natural ingredients and Dead Sea salt, which will clean, hydrate and prevent odour by balancing the pH of the skin at pH 4.5-6.
The natural preservative system is plant-based Leucidal Liquid and phenoxyethanol, which is a nature-identical chemical found in green tea and commercially produced by treating phenol with ethylene oxide in an alkaline medium.
The Dead Sea's mineral composition differs from that of ocean water; the salt in most oceans is approximately 85% sodium chloride while Dead Sea salt is only 12-18% sodium chloride.
Instead the salts contain high concentrations of magnesium, sodium, potassium, calcium, bromide and sulfate ions.
