Low pH Skin Care Compositions And Methods. The present invention is entitle”Low pH Skin Care Compositions and Methods of Using Same”. The present invention discloses an effective low-pH skin care composition that provides good sensory properties and has a low potential for skin irritation. The low pH composition comprises an effective amount of a vitamin B3 compound and optionally one or more additional skin care actives to provide skin health and/or appearance benefits. The low pH composition also comprises a pH buffer comprising lactic acid and sodium lactate, a polymeric thickener comprising polyacrylate crosspolymer-6. A silicone fluid has a kinematic viscosity of 100 cSt or less at 25°C. The pH of the low pH composition may be in the range of 2.0 to 5.0. Classifications A61K8/8152 Homopolymers or copolymers of esters, eg (meth)acrylic acid esters.
Skin Care Compositions Low pH Skin Care Compositions And Methods
Compositions of derivatives of such polymers View 19 more classifications ChakravatiJ ZhukovskyCurrent Assignee Procter Soothely Neck Massager and Gamble Co Worldwide applications 2020 US 2021 JP CA EP KR US CN KR WO US Application. 6A events Priority claim from Application file by Procter and Gamble Co 2021-09-17 Publication of Status Pending InfoPatent citations (633) Non-patent citations (1) Legal events Similar documents Priority and Relate ApplicationsExternal linksEspacenetGlobal DossierDiscuss Description Low pH skin care compositions and methods of use thereof technical field The present invention generally relates to lactic acid/sodium lactate buffer systems for low pH skin care compositions that provide desirable skin sensory properties, good efficacy and have low skin irritation potential.
Low Skin Irritation Potential
More specifically, the present invention relates to low pH skin care compositions comprising a lactic acid/lactate buffer system, a pH stable polymeric thickener, a low molecular weight silicone fluid, and a skincare active. Background technique The skin is the first line of defense against environmental aggressors that would otherwise damage sensitive underlying tissues and organs. Furthermore, the skin plays a key role in the appearance of a person’s body. Not surprisingly, most people want to have healthy, younger-looking skin that provides good barrier protection. And for some, complaining of signs of skin aging such as skin thinning, wrinkles, and age spots are undesire cues of youthful fading. Accordingly, many skin care products are market to address a variety of actual or perceive skin conditions.
Conventional Skin Care Products
Especially those associate with aging and dryness. Conventional skin care products typically contain one or more ingredients to treat a skin condition of concern. For example, US Patent No. 5,968,528 discloses the use of niacinamide for treating signs of skin aging. Typically, cosmetic compositions are formulate to have a slightly acidic to neutral pH (i.e. 5.0 to 7.0). Which is believe to improve the thickening of certain ingredients in the composition (e.g. niacinamide, salicylate, and neutralizing agent) stability. For example, US Patent No. 5,824,666 discloses the challenges of formulating low-pH skin care compositions. However, formulating skin care compositions at low pH (e.g. 2.0 to 5.0) can also provide certain benefits, such as enhancing the acidic mantle of the skin, and exfoliating the skin.
Improving The Appearance Of The Skin
Improving skin texture, and/or providing product formulation flexibility. Accordingly, it would be desirable to provide low-pH skin care compositions for improving the appearance of the skin. It would also be desirable to provide low-pH skin care compositions that are stable and have good sensory properties. Contents of the invention Disclose herein is a low pH skin care composition comprising about 0.1% to 10% of a vitamin B3 compound; about 0.1% to 5% of a pH buffer comprising lactic acid and sodium lactate; about 0.1% to 5% of a pH buffer comprising polyacrylic acid a polymeric thickener of ester crosspolymer-6; and about 0.1% to 10% of a silicone fluid having a kinematic viscosity of 100 cSt or less at 25°C. The pH of the compositions herein is between about 2.0 and about 5.0. In some embodiments.
Method Of Cosmetically Treating Skin
The low pH skin care composition is a serum comprising about 0.1% to 10% vitamin B3 compound; about 0.1% to 5% pH buffer comprising lactic acid and sodium lactate; about 0.1% to 5% % of a polymeric thickener comprising polyacrylate crosspolymer-6; about 0.1% to 10% of a silicone fluid having a kinematic viscosity of 100 cSt or less at 25°C. And wherein the composition has a pH of about 2.0 to about 5.0 and a dynamic viscosity of about 1 cP to about 15000 cP at 25°C. Also, disclose is a method of cosmetically treating skin, the method comprising identifying a target portion of skin in need of treatment; and applying an effective amount of a composition according to claim 1 to the target portion of skin during the treatment period, wherein said composition does not irritate the target skin portion.
Detaile Ways Conventional Skin Care Products
Description of drawings The figure shows the results of the TRPV1 activation assay. Detaile ways Conventional skin care products are typically formulate at neutral pH for a number of reasons. For example, some conventional skin care products will have undesirable organoleptic properties (eg, a runny or sticky feel) and/or exhibit instability (phase separation, cloudiness, etc.) if formulate at low pH. More recently, it has been discovere that certain skincare ingredients such as vitamin B3 compounds and sugars may be more effective at low pH. However, formulating low-pH skin care products can still be challenging. For example, some thickeners tailore for use in low pH compositions, such as those describe in WO20190245011, may impart undesire stickiness when applie to the skin.
When Applie To The Skin
In some instances, low-pH skin care products may be more likely to cause skin irritation (eg, itching, burning, tingling, redness, discoloration, rash, erythema, or peeling) in certain users. Surprisingly, it has now been found that a low-pH skin care composition comprises niacinamide. A polymeric thickener, a low molecular weight silicone oil, and a sodium lactate/lactic acid pH buffer system can provide skincare that is less irritating and has a lower pH than current low pH skin care compositions. Effective skin care products with better sensory properties of the product. Reference in the specification to an “embodiment” or similar means that a particular material, feature, or structure. Characteristic description in connection with the embodiment is include in at least one embodiment, and optionally multiple embodiments.
Although Not Expressly Illustrate
But this does not It is not intende that all embodiments include the describe materials, features, structures, and/or characteristics. Furthermore, materials, features, structures, and/or characteristics may be combine in any suitable manner, and materials, features, structures. Characteristics may be omitte or substitute for those describe in the various embodiments. Accordingly, embodiments and aspects describe herein may include elements or components of other embodiments and/or aspects or may be combine with other embodiments and/or aspects. Although not expressly illustrate in combination, unless otherwise state or declare incompatible. and/or a combination of elements or components of an aspect. In all embodiments, all percentages are by weight of the cosmetic composition unless specifically state otherwise.
All Ratios Are By Weight Unless Specifically
Number representations of significant figures express neither limitations on the quantities shown nor on the precision of the measurements. All numerical values are to be understood as modifie by the word “about” unless specifically indicate otherwise. Unless otherwise indicate, all measurements are understood to be made at about 25°C and at ambient conditions. Where “ambient conditions” means conditions at about 1 atmosphere of pressure and about 50% relative humidity. All numerical ranges are inclusive of narrower ranges; the state upper and lower range limits are interchangeable to form further ranges not expressly recite.
A Human Skin Surface
The compositions of the present invention may comprise, consist essentially of, or consist of the essential components describe herein as well as optional ingredients. As use herein, “consisting essentially of” means that the composition or component may contain additional ingredients so long as the additional ingredients do not materially alter the basic and novel characteristics of the claim composition or method. As use in the specification and the appende claims, the singular forms “a”, “an” and “the” are intende to include the plural forms as well. Unless the context clearly dictates otherwise. The definition “Apply or application” as use with reference to a composition means applying or spreading a composition of the invention onto a human skin surface.
A Positive Beneficial Effect
Such as the epidermis. “Cosmetic agent” means any substance, and any component thereof, which is intende to be rubbe on, poure on, spray on, or spray on. Introduce to, or otherwise applie to the body of a mammal, or any part thereof, to provide a cosmetic effect. Cosmetic agents may contain substances generally recognize as safe (GRAS) by the US Food and Drug Administration, food additives, and materials use in non-cosmetic consumer products, including over-the-counter drugs. “Effective amount” refers to an amount of compound or composition sufficient to substantially induce a positive beneficial effect on keratinous tissue over the course of the treatment period.
Positive Benefits May Be Health
Positive benefits may be health, appearance, and/or sensory benefits including the benefits disclose herein, alone or in combination. In a specific example, the effective amount of the vitamin B3 compound is an amount sufficient to improve the health and/or appearance of psoriatic skin during treatment. In some cases, effective amounts can be demonstrate using ex vivo and/or in vitro methods. “Improving appearance” means providing a measurable, desire change or benefit in skin appearance, which can be quantifie, for example, by a reduction in redness, inflammation, and/or plaque scales. “Low pH” means a pH of less than 5.0 (eg, 1.5 to 4.9, 2.0 to 4.5, 2.5 to 4.0, or 3.5 to 4.0). Suitable methods of determining the pH of the composition are describe in more detail below.
Avoid Serious Side Effects
Neutral pH refers to a pH between 5.0 and 8.0. A “safe and effective amount” means an effective amount of an ingredient (within sound medical judgment) low enough to avoid serious side effects. “Skincare” means regulating and/or improving the condition of the skin. Some non-limiting examples include improving skin appearance and/or feel by providing a smoother, more even appearance and/or feel; increasing the thickness of one or more layers of the skin; improving the elasticity or resilience of the skin; firmness; and reducing the oily, shiny, and/or dull appearance of the skin, improving the hydration status or moisturize status of the skin, improving the appearance of fine lines and/or wrinkles.
Moisturize Status Of The Skin
Improving flaking or desquamation of the skin, making it Plump the skin, improving skin barrier properties, improving skin tone, reducing the appearance of redness or skin rashes, and/or improving the brightness, radiance, or translucency of the skin. “Skin care active” means a compound or combination of compounds that, when applie to the skin, provides immediate and/or long-lasting benefits to the skin or the cell types normally present therein. Skincare actives regulate and/or improve the skin or its associate cells (eg, improve skin elasticity, hydration, skin barrier function, and/or improve cell metabolism). “Skin care composition” means a composition comprising skincare actives that regulate and/or improve the condition of the skin.
Skin Care Active
As use herein, “treatment period” refers to the length of time and/or frequency with which a material or composition is applie to a target skin surface. “Vehicle control” refers to a negative control identical to the test composition, except that it does contain the particular activities of interest (eg, no vitamin B3 compound ). Combination The skin care compositions herein are low pH compositions intende for topical application to human skin to improve skin appearance and/or function. In some instances, the low pH compositions of the present invention may be use in the non-therapeutic treatment of various skin conditions. In some instances, low pH compositions may be particularly suitable for improving hyperpigmente spots.
Various Skin Conditions
Uneven skin tone, and/or pale-looking skin. The low-pH skin care compositions herein comprise a safe and effective amount of a vitamin B3 compound; a polymeric thickener that can tolerate low pH environments; a low molecular weight silicone fluid; and a pH buffering system comprising lactic acid and sodium lactate. The compositions may optionally contain silicone emulsifiers as well as other ingredients normally present in topical skin care compositions. Without being bound by theory, it is believe that the combination of these ingredients provides an effective skin care composition that has good sensory properties and is mild to the skin. The cosmetic skin care compositions herein can be prepare by admixing the ingredients with a dermatologically acceptable carrier using conventional methods known to those skille in the art.
Lotion Skin Care Compositions
The compositions can be provide in various product forms such as solutions, suspensions, emulsions, creams, gels, toners, bars, sprays, aerosols, ointments, cleansing liquids Detergents and solid bars, pastes, foams, mousses, shaving creams, wipes, bars, patches, power patches, hydrogels, film-forming products, facial and skin masks (with and without insoluble sheet), etc. The form of the composition may conform to the particular dermatologically acceptable carrier selection. In some cases, the compositions herein may be in the form of serums. Serums are in the form of topical skin care compositions in relatively concentrate formulations. Which generally have a lower viscosity than conventional cream or lotion skin care compositions.
Consumers Desire Skincare
In some cases, serums may be provide in the form of low-viscosity liquids that are markete to specifically target specific skin conditions and/or for use in the first step of a skin care regimen. The serum products herein can have a dynamic viscosity at 25° C. of 1 centipoise (cP) to 15,000 cP (eg, 50 cP to 10,000 cP, or 100 cP to 7,500 cP, 200 cp to 5,000 cp, or 300 cp to 2,500 cp). The viscosity of the low pH compositions herein can be determine according to the Rheology Method provide in the Methods section below. It has been found that at least some consumers desire skin care serums with a certain balance of clarity and opacity. If the serum is too clear, it will look too watery and the consumer may doubt the efficacy of the product.
The Opacity Test Describe
But if the serum is too opaque, the consumer may think that the product will not provide the refreshing, clean feeling expect from a serum. Accordingly, the low pH serum products herein have a pH value between 45 and 85 (e.g. between 50 and 81, between 55 and 77, or even according to the Opacity Test describe in more detail below). Between 60 and 73) the opacity. In some cases, it may be desirable to limit the number of hydrocarbon oils (such as fatty alcohols) and mineral oils present in low-pH serums, as these ingredients can significantly increase the opacity of the serum. Accordingly, it may be desirable to provide a low-pH serum that is free or substantially free of hydrocarbon oil (eg, less than 3%, 2%, 1%, 0.5%, or even 0%).
The Present Invention Comprise A Safe
Vitamin B3 Compound Compositions of the present invention comprise a safe and effective amount of a vitamin B3 compound for regulating various skin conditions, eg, as describe in US Patent No. 5,939,082. The compositions herein may contain from 0.1% to 10% by weight (eg, 0.5% to 5% or 1% to 4%) of a vitamin B3 compound, base on the weight or volume of the composition. As use herein, “vitamin B3 compound ” refers to a compound having the formula: Figure ( ie, niacinamide), COOH (ie, niacin), or CH2OH ( ie, nicotinic alcohol); derivatives thereof; and salts of any of the foregoing. Exemplary derivatives of vitamin B3 compounds include nicotinic acid esters, including non-vasodilating nicotinic acid esters e.g.
Improve Efficacy At Lower PH
Tocopheryl nicotinate, myristyl nicotinate, nicotinamide riboside, nicotine amino acid, nitinol esters of carboxylic acids, nicotinic acid N-oxide, and nicotinamide N-oxide. In some instances, vitamin B3 compounds such as niacinamide may have improve efficacy at lower pH, eg, as describe in US Patent Publication No. 2020/0009123. In some instances, it may be desirable for the ring nitrogen of the vitamin B3 compound to be “uncomplexe” (e.g. chemically unbound and/or unhindere) in the composition and/or prior to application to the target skin surface. ). For example, the compositions herein can be free or substantially free (ie, less than 3%, 2%, 1%, or even less than 0.5%) of salts or complexes of vitamin B3 compounds.
Use In Skin Care Compositions
Exemplary methods of minimizing or preventing undesire salt and/or complex formation include excluding substances from the composition that form substantially irreversible complexes or other undesire complexes with the vitamin B3 compound, pH adjustment, ionic strength adjustment, use of surfactants, and implementation of formulation procedures wherein the vitamin B3 compound and the species complex therewith are in different phases. Low pH acid buffer system A variety of acids are known for use in skin care compositions. For example, alpha hydroxy acids (eg, citric acid, glycolic acid, malic acid, and lactic acid). Beta hydroxy acids (eg, salicylic acid and propionic acid), and polyhydroxy acids (eg, gluconic acid) are commonly use as exfoliating agents.
Lactic Acid May Provide Skin Benefits
However, some acids are stronger than others, and/or some people may be more sensitive to certain concentrations of acids than others. Both of these factors may increase the risk of skin irritation cause by low-pH compositions containing acids. Lactic acid is one of the milder alpha hydroxy acids when it comes to skin irritation, but is still strong enough to provide the desire low pH in the compositions of the present invention. In addition, lactic acid may provide skin benefits not provide by other alpha hydroxy acids (eg, glycolic, citric, or malic acid). For example, lactic acid may help improve the skin’s natural moisture factor and/or stimulate collagen turnover to help improve signs of aging skin.
Improve Signs Of Aging Skin
Accordingly, the compositions herein comprise lactic acid in an amount and concentration to provide the desire low pH to the skin care compositions herein. In some cases, the low pH compositions herein can comprise 0.5% to 5% lactic acid and/or gluconic acid (eg, 0.75% to 4%, 1% to 3%, or 1.5% to 2.5%). When providing low pH compositions for topical application to the skin, it is important to include a buffer to help maintain the pH of the composition after application to the skin. On average, human skin pH typically ranges from about 5.0 to 6.0. To maintain this pH, human skin has evolve a natural buffer system that resists pH changes. Thus, when a low-pH composition is applie to the skin. The skin’s natural buffer system will attempt to adjust the pH of the composition to match the skin’s natural pH.
Provide Desire Skincare Benefits
Without the addition of buffering agents, low pH compositions may not provide desire skincare benefits. The low pH compositions herein comprise sodium lactate and/or sodium gluconate buffers, depending on the acid or acids use to lower the pH in the composition. Sodium lactate and/or sodium gluconate buffers may be suitable for maintaining the pH of the composition of the invention at a desire level after application to the skin and for at least 1 minute thereafter (e.g. 5, 10, 15, 30, 60 minutes after application). or even 120 minutes or longer) in any amount to provide sufficient time for the active ingredients in the composition to penetrate into the skin. In some cases, sodium lactate can be present in the low pH composition in an amount of 0.25% to 4% (eg, 0.5% to 3%, 0.75% to 2%, or 1% to 1.75%).
Help Moisturize The Skin
In some cases, the salt buffer may be present in a weight ratio of acid to buffer of 1:10 to 10:1. It may be desirable to use the L-enantiomer form in acid and/or salt buffers, as this is the form that occurs naturally in the body. In addition to acting as a buffer, sodium lactate acts as a humectant to help moisturize the skin, making it a particularly suitable buffer. Of course, it should be understood that the compositions of the present invention may optionally contain other pH buffers known for use in skin care compositions. Thickener The composition includes a polymeric thickener that can withstand the low pH electrolytic environment. That is, the thickener will not lose its ability to thicken or stabilize the composition at low pH in the presence of an acid-salt buffer system.
Combinations Of Acids And Salts
Some conventional neutralize thickeners are known to degrade and/or lose the ability to properly thicken compositions at lower pH and/or in the presence of acid-salt buffers (eg sodium lactate). For example, some neutralize thickeners degrade in low-pH environments. On the other hand, fatty alcohol thickeners such as cetyl and stearyl alcohols are generally stable at low pH but tend to impart undesirable cloudiness or Opacity. It has also been found that certain anionic polymeric thickeners can provide adequate resistance to low-pH environments. But cannot tolerate buffer systems due to combinations of acids and salts. Thus, in some cases, the low pH compositions describe herein may be free or substantially free of neutralize thickeners, fatty alcohol thickeners, and anionic thickeners.
Combination Include Natural
The thickener can be present in an amount of 0.0001% to 25% (eg, 0.001% to 20%, 0.01% to 10%, 0.5% to 7%, or 1% or 5%) by American Beauty weight of the composition. Other non-limiting examples of thickeners or water structures that may be use herein alone or in combination include natural or synthetic gums. Polysaccharides, carboxylic acid polymers, polyacrylamide polymers, sulfonate polymers, and copolymers of this thing. Additional examples include modify gums, cellulose, and superabsorbent polymers. The term “superabsorbent polymer” is understood to mean a polymer capable of spontaneously absorbing at least 20 times its own weight in aqueous fluid. In particular water and especially distille water, in its dry state.