EA035754B1 - Soap bar composition and methods for maintaining enhanced lather in presence of water with high electrolyte concentration - Google Patents

Abstract

The invention relates to soap bar compositions for enhancing lather when washing in water having water hardness greater than about 25 g/l of water, wherein said bar comprises: a) 30-90% by weight of bar composition alkali metal or alkanol ammonium salt fatty acid soap, wherein: (i) ratio of Cacid soap to Cacid soap is about 0.5:1.0 to about 1.5:1.0; (ii) wherein amount of Cacid is 0 to about 3.5% by weight of bar composition; (iii) amount of oleic acid is about 25 to 35% by weight of bar composition; and (iv) amount of unsaturated Cacid other than oleic acid is 0 to about 5% by weight of bar composition; b) about 0.1 to about 15% by weight of bar composition polyol; c) about 0.1 to 25 wt.% mineral or organic particles; and d) about 10 to 30 wt.% water. The invention also relates to a method of enhancing foam in water of water hardness greater than about 25 g/l using said bar.

Description

State of the art

Toilet bar soaps are usually made by saponification (eg, neutralization) of triglyceride / fatty acids. In this saponification process, various fats (for example, mixtures of tallow, palm and coconut oils) are saponified in the presence of an alkali (usually NaOH) to produce alkaline fatty acid salts (derived from fatty acid chains that form glyceride) and glycerol. Glycerin can optionally be extracted with saline (eg water with a high sodium ion concentration) to obtain a dilute fatty acid soap solution containing soap and an aqueous phase (eg 70% soap and 30% aqueous phase). The soap solution is then typically dried (eg, to about 12% water) and the resulting mass is ground in a mill, passed through a worm press, and punched into pieces. Alternatively, the soap solution can be cast into molds, blisters, etc.

The chain length of fatty acid soaps varies depending on the starting fats or oils (for the purposes of this disclosure, oil and fat are used interchangeably unless the context requires otherwise). Soaps of longer chain fatty acids (e.g., based on C ₁₆ palmitic acid or a C ₁₈ stearic acids) are usually obtained from tallow and palm oils, and soaps of shorter chain (e.g., based on C ₁₂ lauric acid), normally can be obtained, for example, from coconut oil or palm kernel oil. The resulting fatty acid soaps can also be saturated or unsaturated (eg, oleic acid).

Typically, soaps of fatty acids with higher molecular weight (e.g., soaps of C14-C ₂ 2-acids) are insoluble and do not form a foam, although they may contribute to the foam other soluble soaps with a creamy texture and a greater stability. At the same time, soaps with a lower molecular weight (for example, based on C ₈ -C ₁₂ -acids) rapidly foaming. However, longer chain soaps are preferred because they retain their structure and do not dissolve as easily. Unsaturated soaps (such as those based on oleic acid) are soluble and foam quickly, like short chain soaps, but produce a thicker, creamier lather like longer chain soaps. The specific mixture of soaps based on fatty acids with different chain lengths has a huge impact on the quality of the lather.

In general, it is considered extremely difficult to obtain a clean bar soap with improved foaming properties (e.g., fast foaming), in particular because of the required structural characteristics required to obtain a solid bar soap and maintain its structure (since structuring is provided by soaps with longer chain length).

When a synthetic surfactant (e.g., a nonionic surfactant) is added to increase softness, the bar soap will usually still need to be prepared using predominantly long-chain soaps to ensure that the soap has good structural characteristics and maintains these structural characteristics during the stamping process.

For example, WO 93/04161 (P&G) discloses a soap bar containing mixtures of soap, a C1 ₄ -C ₂₀ alkyl polyethoxylate nonionic surfactant and a C1 ₆ -C1 ₈ acyl isethionate (also a mild surfactant). The soap used contains at least tallow (longer chain, slower foaming) and includes cationic polymeric additives for softening the skin and free fatty acids as moisturizers.

Foaming occurs even worse in water containing mono- and bivalent electrolytes (for example, a compound of sodium, calcium, magnesium). This high electrolyte water (also known as hard water or salt water) is common in many parts of the world. As indicated, mass bar soap is currently not effective in salt water due to the precipitation of more soluble soaps (usually short chain C ₈ , Xu, C ₁₂ soaps) by divalent salts such as calcium and magnesium salts present in said salt water. water. In addition, in laboratory tests, it has been found that the presence of monovalent ions (for example, sodium ions), also contained in salt water, has a negative effect. In particular, monovalent ions appear to interfere with micelle formation and thus negatively affect foam formation.

In general, the use of specially formulated soaps (which involved additional costly processing) and / or the use of additional costly co-actives have been proposed in the art to address poor foaming problems.

For example, in US patent No. 5540852, Kefauver et al., Proposed a composition of mild lathering bar soap for personal care, containing from 30 to 85 mass. a specially formulated fatty acid soap, which in turn contains 50 to 85% saturated fatty acid soap selected from the group consisting of myristic, palmitic and stearic acid soaps. Kefauver does not disclose specific ratios of capri soaps

- 1,035754 new and lauric fatty acids, as well as maximum amounts of myristic fatty acid or maximum amounts of C ₁₈ unsaturated acids other than monounsaturated oleic acid.

US Pat. No. 5,656,579 to Chambers et al. Discloses a mild toilet bar soap containing mixtures of soaps with one or more co-active ingredients containing at least 25% lauric acid soaps by weight of all active ingredients. In addition, Chambers not disclose bar soap compositions containing a maximum amount of soaps of myristic acid or an unsaturated _C18-acids, other than oleic acid in combination with soaps ratios based on lauric and capric fatty acids claimed in this invention.

Previous attempts to improve softness and / or performance have involved special optimization or the use of expensive co-actives.

In the concurrently pending applications of the present applicants No. 13/625273 and 13/922764, the applicants proposed specific mixtures of fatty acids, where the ratios of C ₈ -C ₁₀ acid soaps to C ₁₂ acid soap are specified and the maximum amount of C _{14 is} disclosed -acids.

In the present invention, Applicants have found that a soap bar similar to that proposed in the aforementioned pending applications (with different key characteristics) can be used to improve foaming in water with a high concentration of electrolytes (for example, bar soaps with a high predetermined water hardness ).

Since fresh water makes up only a small part of the water on the planet (1.75% frozen and 0.75% in aquifers, natural lakes, reservoirs, in the form of rain), and the rest (97.5%) is salty, it is important to provide the possibility of obtaining lumpy soap that foams well in hard water.

Brief description of the invention

More specifically, in the present invention, Applicants have surprisingly found that by varying the ratio of short chain fatty acids (e.g., the ratio of C ₁₀ acid to C ₁₂ acid using no more than a certain maximum amount of C ₁₄ acid and using specific amounts and types of unsaturated C _18- acids), a rich foam can be obtained even in water with a high concentration of electrolytes (for example, characterized by a hardness value of more than about 25 g of salt per liter of water, preferably more than about 50, preferably more than about 75; seawater hardness is about 635 g of salt per 1 liter of water).

Detailed description of the invention

The present invention relates to a bar soap composition that improves foaming in water having a high electrolyte concentration (eg, having a hardness greater than about 25 g of salt per liter of water). Bar soap compositions contain:

a) a mixture of soaps based on fatty acids in an amount of 30 to 90% by weight of the bar soap, where:

i) the ratio of C ₁₀ fatty acid to C ₁₂ fatty acid is from about 0.5: 1.0 to about 1.5: 1.0, preferably from about 0.75: 1 to 1.25: 1, more preferably about 1: 1;

ii) the amount of fatty acid with a chain length of C ₁₄ is up to about 3.5%, preferably from about 0.1 to about 3.0% by weight of the bar composition;

iii) the amount of oleic acid is from about 25 to about 35% of the bar soap composition;

iv) the amount of Cj ₈ unsaturated fatty acid other than oleic acid is up to about 5%;

b) from about 0.1 to about 15% polyol by weight of the composition;

c) from about 0.1 to about 25%, preferably from 0.1 to 15% of mineral or organic particles by weight of the composition; and

d) from about 10% to 30%, preferably from 13 to 20%, water.

In a second embodiment, the present invention relates to a method for improving foaming in water containing a high amount of dissolved salt, in particular divalent salts such as calcium and magnesium salts, and monovalent salts such as sodium salts (i.e., in water with a high electrolyte content ). Preferably, foaming is improved when used in water having a hardness greater than about 25 g salt / L of water, more preferably greater than about 50 g salt / L. This method involves producing a foam in water with a specified hardness using the bar soap composition above, providing improved foaming (for example, an improvement in foaming by more than about 30%) compared to foam formed using a bar soap having different from the claimed above the C ₄₀ : Ci ₂ ratio for mixtures of fatty acids, the maximum amounts of C1 ₄ acid and the maximum amounts of unsaturated C18 acid.

When using a bar soap having a ratio of palm oil to palm stearin to palm kernel oil (PNO) of 60:40, i.e. soap that has been specially formulated (designed) in such a way that the distributions along the chain length are the distributions indicated above,

- 2,035754 foam values (measured in millimeters using a SITA® foam tester, such as the SITA® Foam Tester R-2000, or in the quantitative evaluation test defined in the protocol) will be greater than about 30%, preferably more than about 40% higher than bar soaps with the same 60:40 ratio of the same oils, but where the chain length ratios and maximum values for some fatty acids (C ₁₄ acid; unsaturated C ₁₈ acid other than oleic acid) are not as specifically defined in the present invention.

Bar soap composition.

The present invention relates to an extruded or melt-cast personal care bar containing specific amounts and ratios of various fatty acid soaps; optionally, one or more added polyols, polymers, organic and inorganic adjuvants, electrolytes, beneficial agents and other auxiliary ingredients, and the rest is water. These components of the bar soap composition that are used to make and evaluate the bar soap are described below. The bar soap compositions of the present invention can be made by methods that generally include extrusion molding of castings or preforms and stamping or pressing in molds of said preforms to form individual bars, bars, or bars, alternatively, said products can be prepared by melt casting.

A mixture of soaps based on fatty acids.

Fatty acid soaps, other surfactants, and essentially all of the ingredients in a bar soap should be suitable for normal human skin contact and preferably result in a bar soap having a generous foaming effect. The soap bar produces excellent lather even when washed in water with a high concentration of divalent and monovalent metal salts. This lather is compared to a lather lather made from the same oil base, but where the fatty acids have not been optimized as defined in the present invention. The improvement in foaming is greater than about 30%, preferably greater than about 40%, compared to non-limiting bar soap (see comparative bar soap in the example). This is true either for the quantitative test defined in the protocol or for the quantitative data of the SITA® foam tester obtained as also defined in the protocol.

The bar soap composition, which provides improved foaming, contains soap based on a mixture of fatty acids in an amount of from 30 to 85% by weight of the bar soap. More preferably, the fatty acid mixture comprises a fatty acid mixture in an amount of 40 to 80% by weight of the bar soap. Most preferably, the fatty acid mixture comprises a fatty acid mixture in an amount of 45 to 78% by weight of the bar soap.

The fatty acid mixture includes one or more surfactants. The preferred type of surfactant is a fatty acid soap. In the present description, the term soap is used in the conventional sense, i.e. alkali metal or alkanolammonium salts and aliphatic alkane or alkene monocarboxylic acids. Sodium, potassium, magnesium, mono-, di- and triethanolammonium cations or combinations thereof are most suitable for the purposes of the present invention. In general, sodium soaps are used in the compositions of the present invention, but no more than about 15% of the soap can be potassium, magnesium, or triethanolamine soaps. Soaps suitable for use in the present invention are well known salts of alkali metals and natural or synthetic aliphatic (alkanoic or alkene) acids containing from about 8 to about 24 carbon atoms. These salts can be described as alkali metal carboxylates formed by carboxylic acids with saturated or unsaturated hydrocarbon chains containing from about 8 to about 24 carbon atoms. Alkali metal salts are preferred.

The mixture of fatty acids are prepared from fatty acids which may be various fatty acids, typically fatty acids containing fatty acid moieties with a chain length of C8 to C _24. The fatty acid mixture may also contain relatively pure amounts of one or more fatty acids. Suitable fatty acids include, but are not limited to, butyric, nylon, caprylic, capric, lauric, myristic, myristaidic, pentadecanoic, palmitic, palmitoleic, margaric, heptadecene, stearic, oleic, begadoleic, linolenic, linoleic, linoleic, linoleic, and their isomers. It is preferable to minimize or eliminate the amount of butyric and nylon acids. In preferred embodiments of the present invention, the fatty acid mixture comprises fatty acids with fatty acid chain lengths of 10 carbon atoms (capric acid) and 12 carbon atoms (lauric acid), used in specific proportions. In preferred embodiments of the present invention, the fatty acid mixture comprises a low level of a fatty acid with a saturated fatty acid moiety chain length,

- 3 035754 constituting 14 carbon atoms (myristic acid).

The mixture of fatty acids according to the present invention contains relatively high amounts (for example, at least 3%, preferably at least 10% by weight of the bar soap composition) capric and lauric acids, while the ratio of Cio acid to C ₁₂ acid is in the given range. More specifically, C8-C ₁₄ fatty acid should be from about 10 to about 32% by weight of the composition (taken separately C ₁₄ -acid is not more than about 3.5% by weight of the composition); C ₁₆ -C ₁₈ -acids with a long saturated chain should make up from about 15 to 55% by weight of the composition; and C ₁₈ -acids with a long unsaturated chain (e.g. oleic acid) should be from about 11 to 42% by weight of the composition (unsaturated C ₁₈ -acid other than oleic acid is 10% or less by weight of the composition, preferably 8 .% or less, even more preferably 5 wt.% or less). Taken together, these critical values provide superior lather in water with a high electrolyte content compared to bar soaps with the same oil base where critical conditions (eg optimization or design of chain lengths) are not met.

In a preferred embodiment of the present invention, the fatty acid mixture may have a ratio of capric acid to lauric acid ranging from 0.5: 1 to 1.5: 1. Preferably, the ratio is between 0.75: 1 and 1.25: 1.

Finally, the fatty acids can be in the form of free fatty acids, preferably in an amount not exceeding 5% of the mixture of fatty acid soaps.

Organic and inorganic adjuvant materials.

The total amount of adjuvant materials used in the bar soap composition should not exceed 50% by weight of the bar soap composition.

Suitable starchy materials that can be used include natural starch (from corn, wheat, rice, potato, tapioca, etc.), pregelatinized starch, various physically and chemically modified starch, and mixtures thereof. The term natural starch means starch that has not been chemically or physically modified, also known as raw or native starch.

The preferred starch is natural or native starch from maize (corn), cassava, wheat, potatoes, rice and other natural sources. Crude starch with varying ratios of amylose to amylopectin: eg maize (25% amylose); waxy maize (0%); maize high in amylose (70%); potatoes (23%); rice (16%); sago (27%); cassava (18%); wheat (30%), etc. The crude starch can be used directly or modified during the preparation of the bar soap composition so that the starch becomes either partially or completely gelatinized.

Another suitable starch is pregelatinized starch, which is starch that has been gelatinized before being added as an ingredient in the bar soap composition of the present invention. Various types of starch are available that will gelatinize at different temperatures, such as cold water dispersible starch. One suitable commercial pregelatinized starches are available from National Starch Co. (Brazil) under the trademark FARMAL® CS 3400, but other commercially available substances with similar characteristics are suitable.

Polyol.

Another organic adjuvant could be a polyol or a mixture of polyols. The term polyol is used herein to mean a compound containing multiple hydroxyl groups (at least two, preferably at least three), which is highly soluble in water, preferably freely soluble in water.

Many types of polyols are available, including relatively low molecular weight, short chain polyhydroxy compounds such as glycerol and propylene glycol; sugars such as sorbitol, mannitol, sucrose, and glucose; modified carbohydrates such as hydrolyzed starch, dextrin and maltodextrin; and polymeric synthetic polyols such as polyalkylene glycols such as polyoxyethylene glycol (PEG) and polyoxypropylene glycol (PIT).

Particularly preferred polyols are glycerin, sorbitol, and mixtures thereof.

The polyol level plays a critical role in forming a thermoplastic mass that is suitable for both high-speed production (300-400 soap bars / min) and personal care bar soap. It has been found that when the polyol level is too low, the stock is not pliable enough at the extrusion temperature (eg, 40 to 45 ° C), and the bar soap generally exhibits greater softening and higher consumption rates. Conversely, when the polyol level is too high, the mass becomes too soft to form soap bars at high speed at normal process temperatures.

In a preferred embodiment of the present invention, the soap bar according to the present invention contains from 0.1 to 20%, preferably from 0.5 to 15% by weight of the polyol. As noted, preferred polyols include glycerin, sorbitol, and mixtures thereof.

- 4 035754

The adjuvant system may optionally include insoluble particles containing one substance or a combination of substances. Insoluble particles are substances that are in the form of solid particles and are suitable for personal hygiene. Preferably mineral (eg inorganic) or organic particles are present.

Insoluble particles should not feel rough or grainy and therefore should be less than 300 microns, more preferably less than 100 microns, and most preferably less than 50 microns.

The preferred inorganic particulate material includes talc and calcium carbonate. Talc is a magnesium silicate mineral with a sheet silicate structure and composition Mg ₃ Si ₄ (OH) 22 and can be available in hydrated form. It has a lamellar morphology and is substantially oleophilic / hydrophobic, i. E. moistened with oil, not water.

Calcium carbonate or chalk exists in three crystalline forms: calcite, aragonite, and vaterite. The natural morphology of calcite is rhombohedral or cuboid, acicular or dendritic in the case of aragonite, and spherical in the case of vaterite.

Commercial calcium carbonate or chalk, known as precipitated calcium carbonate, is produced by a carbonation method in which carbon dioxide is bubbled through an aqueous slurry of calcium hydroxide. In this process, the crystalline form of calcium carbonate is calcite or a mixture of calcite and aragonite.

Examples of other optional insoluble inorganic particulate materials include aluminosilicates, aluminates, silicates, phosphates, insoluble sulfates, borates, and clays (eg, kaolin, white clay) and combinations thereof.

Particulate organics include insoluble polysaccharides such as highly crosslinked or rendered insoluble starch (eg, by reaction with a hydrophobic substance such as octyl succinate) and cellulose; synthetic polymers such as various lattices and suspension polymers; insoluble soaps and mixtures thereof.

The bar soap compositions preferably contain from 0.1 to 25%, preferably from 5 to 15%, of said mineral or organic particles, based on the weight of the bar soap composition.

Water.

The bar soap according to the present invention contains 10 to 30 wt%, preferably 13 to 20 wt% water.

Optional ingredients.

Synthetic surfactants.

The bar soap compositions may optionally contain synthetic type surfactants (detergents) other than the soap — so-called syndets (synthetic detergents). Syndyts can include anionic surfactants, nonionic surfactants, amphoteric or zwitterionic surfactants, and cationic surfactants.

The amount of synthetic surfactant present in the bar soap is generally less than 25%, preferably less than 15%, preferably not more than 10%, and most preferably 0 to 7%, based on the total weight of the bar soap composition.

The anionic surfactant may be, for example, an aliphatic sulfonate, such as a primary alkane (e.g., _C8-C22) sulfonate, primary alkane (e.g., C8-C22) disulfonate, C-C ^ alkensulfonat, CVC'22 -hydroxyalkanesulfonate or alkylglyceryl ether sulfonate (AGS, AGS); or an aromatic sulfonate such as an alkyl benzene sulfonate. Alphaolefin sulfonates are other suitable anionic surfactants.

The anionic surfactant can also be an alkyl sulfate (eg, C1 ₂ -C18 alkyl sulfate), in particular primary alcohol sulfate or alkyl ether sulfate (including alkyl glyceryl ether sulfates).

The anionic surfactant can also be a sulfonated fatty acid such as alpha-sulfonated tallow fatty acid, an ester of a sulfonated fatty acid such as alpha-sulfonated methyl tallowate, or mixtures of these compounds.

The anionic surfactant can also be alkyl sulfosuccinates (including mono- and dialkyl, for example C ₆ -C ₂₂ sulfosuccinates), alkyl and acyl taurates, alkyl and acyl sarcosinates, sulfoacetates, C8-C22 alkyl phosphates and phosphates, alkyl phosphate ethers and alkoxylalkyl phosphate esters, acyl lactates or lactylates, C ₈ -C ₂₂ monoalkyl succinates and maleates, sulfoacetates and acyl isethionates.

Another class of anionic surfactants are C-Cc-alkyl ethoxycarboxylates (1-20 EO).

Other suitable anionic surfactants are C — C ^ acyl isethionates. These esters are prepared by the reaction between the isethionate

- 5,035754 alkali metal and mixed aliphatic fatty acids containing from 6 to 18 carbon atoms and having an iodine number of less than 20. At least 75% of the mixed fatty acids contain from 12 to 18 carbon atoms and not more than 25% contain from 6 to 10 carbon atoms. The acyl isethionate can also be alkoxylated isethionates.

The acyl isethionates, if present in the composition, will generally be present in an amount in the range of about 0.5 to about 25 weight percent of the total composition.

In general, the anionic component will constitute the majority of the synthetic surfactants used in the bar soap composition.

Amphoteric detergents that can be used in the present invention contain at least one acidic group. The specified group can be a carboxylic acid or sulfonic acid group. These detergents contain quaternary nitrogen and therefore are quaternary amido acids. Typically they should contain an alkyl or alkenyl group of 7 to 18 carbon atoms. Suitable amphoteric surfactants include amphoacetates, alkyl and alkyl amido betaines, and alkyl and alkyl amido sulfobetaines.

It is contemplated that amphoacetates and diamphoacetates are also potential zwitterionic and / or amphoteric compounds that can be used.

Suitable nonionic surfactants include the reaction products of compounds containing a hydrophobic group and a reactive hydrogen atom, for example aliphatic alcohols or fatty acids, with alkylene oxides, in particular ethylene oxide, either alone or with propylene oxide. Examples include condensation products of aliphatic (C8-C18) primary or secondary linear or branched alcohols with ethylene oxide and products obtained by condensation of ethylene oxide with the reaction products of propylene oxide and ethylenediamine. Other so-called nonionic detergent compounds include long chain tertiary amine oxides, long chain tertiary phosphine oxides, and dialkyl sulfoxides.

Nonionic compounds can also be sugar amides such as alkyl polysaccharides and alkyl polysaccharide amides.

Examples of cationic detergents are quaternary ammonium compounds such as alkyldimethylammonium halides.

Other surfactants that can be used are described in US Pat. No. 3,723,325, Parran Jr., and Surface Active Agents and Detergents (Vol. I & II) Schwartz, Perry & Berch, which are also incorporated herein by reference.

Finishing adjuvant substances.

These substances are ingredients that improve the aesthetic qualities of the bar soap, in particular the visual, tactile properties, and aroma, directly (fragrances) or indirectly (preservatives). A wide variety of optional ingredients can be included in a bar soap composition of the present invention. Examples of adjuvants include, but are not limited to, perfume; opacifying agents such as fatty alcohols, ethoxylated fatty acids, solid esters and TiO ₂ ; dyes and pigments; a pearlescent agent such as TiO ₂ coated mica and other interference pigments; plate-like specular particles such as organic sheen; skin sensation modulating ingredients such as menthol and ginger; preservatives such as dimethyldimethylhydantoin (Glydant XL1000), parabens, sorbic acid and the like; antioxidants such as, for example, butylated hydroxytoluene (BHT); chelating agents such as salts of ethylenediaminetetraacetic acid (EDTA) and trisodium etidronate; emulsion stabilizers; auxiliary thickeners; buffering agents and mixtures thereof.

The amount of pearlescent agent should be from about 0.1 to about 3%, preferably from 0,% to 0.5%, and most preferably from about 0.2 to about 0.4%, based on the total weight of the bar soap composition.

Agents with beneficial effects on the skin.

A special class of optional ingredients, which is of great importance in this document, are agents that have a beneficial effect on the skin, included for promoting the health and condition of skin and hair. Potential skin benefit agents include, but are not limited to, lipids such as cholesterol, ceramides, and pseudoceramides; antimicrobial agents such as triclosan; sunscreens such as cinnamates; other types of exfoliating particles such as polyethylene granules, walnut shells, apricot pits, flower petals and seeds, and inorganic substances such as silicon dioxide and pumice; additional emollients (skin softening agents) such as long-chain alcohols and waxes such as lanolin; additional humidifiers; means for increasing skin tone; skin nutrients such as vitamins such as vitamins C, D and E, and essential oils such as bergamot, citrus unshiu, calamus and the like; water-soluble or water-insoluble extracts of avocado, grape, grape seed, myrrh, cucumber, watercress, calendula, black elderflower, geranium, lime blossom, amaranth, sea water

- 6 035754 grown-ups, ginkgo, ginseng, carrots; touch-sensitive balsamic, camu camu, alpina leaf and other plant extracts such as witch hazel extract, and mixtures thereof.

The composition can also contain a number of other active ingredients that provide additional beneficial effects on the skin (including scalp). Examples include anti-acne agents such as salicylic acid and resorcinol; sulfur-containing D- and L-amino acids and their derivatives and salts, in particular their N-acetyl derivatives; anti-wrinkle, anti-atrophy and skin regeneration active substances such as vitamins (eg A, E and K), vitamin alkyl esters, minerals, magnesium, calcium, copper, zinc and other metal components; retinoic acid and its esters and derivatives such as retinal and retinol, vitamin B3 compounds, alpha hydroxy acids, beta hydroxy acids, for example salicylic acid and its derivatives; skin soothing agents such as aloe vera, jojoba oil, propionic and acetic acid derivatives, phenamic acid derivatives; artificial tanning agents such as dihydroxyacetone; tyrosine; tyrosine esters such as ethyl tyrosinate and glucose tyrosinate; skin lightening agents such as aloe extract and niacinamide, alpha-glyceryl-B-ascorbic acid, aminothyroxine, ammonium lactate, glycolic acid, hydroquinone, 4-hydroxyanisole, sebum stimulating agents such as brionolic acid, dehydroepiandroster ) and oryzanol; inhibitors of sebaceous secretion such as aluminum hydroxychloride, corticosteroids, dehydroacetic acid and its salts, dichlorophenylimidazole dioxolane (available from Elubiol); antioxidant agents, protease inhibitors; skin tightening agents such as terpolymers of vinylpyrrolidone, (meth) acrylic acid and a hydrophobic monomer composed of long chain alkyl (meth) acrylates; antipruritic agents such as hydrocortisone, methdilizine and trimeprazine, agents for inhibiting hair growth; 5-alpha reductase inhibitors; agents that enhance flaking; anti-glycation agents; anti-dandruff agents such as zinc pyridinethione; hair growth promoting agents such as finasteride, minoxidil, vitamin D analogs and retinoic acid, and mixtures thereof.

Electrolyte.

The bar soap contains from 0.5 to 5 wt% electrolyte. Preferred electrolytes include chlorides, sulfates and phosphates of alkali or alkaline earth metals. Without wishing to be bound by any particular theory, it is believed that the electrolytes aid in structuring the solidified mass of soap and also increase the viscosity of the molten mass due to the usual ionic effect. The bar soap used for comparison was found to be softer without any electrolyte. Sodium chloride and sodium sulfate are the most preferred electrolytes, more preferably in an amount of 0.6 to 3.6 wt%, and most preferably in an amount of 1.0 to 3.6 wt%.

Polymers.

The bar soap may contain from 0.1 to 5% by weight of a polymer selected from acrylates or cellulose ethers. Preferred acrylates include crosslinked acrylates, polyacrylic acids, or sodium polyacrylates. Preferred cellulose ethers include carboxymethyl cellulose or hydroxyalkyl cellulose. You can also use a combination of these polymers, provided that the total amount of polymers does not exceed 5 wt.%.

Acrylates.

The preferred soap bar contains from 0.1 to 5% acrylates. A more preferred soap bar contains 0.15 to 3% acrylates. Examples of acrylate polymers include polymers and copolymers of acrylic acid crosslinked with polyallyl sucrose as described in US Pat. No. 2,798,053, which is incorporated herein by reference. Other examples include polyacrylates, acrylate copolymers or alkali swellable emulsion acrylate copolymers (e.g. ACULYN® 33 from Rohm and Haas; CARBOPOL® Aqua SF-1 from Lubrizol Inc.), hydrophobically modified alkali swellable copolymers (e.g. ACULYN® 22, ACULYN® 28 and ACULYN® 38 from Rohm and Haas). Commercially available crosslinked acrylic acid homopolymers include CARBOPOL® 934, 940, 941, 956, 980 and 996 carbomers available from Lubrizol Inc. Other commercially available crosslinked acrylic acid copolymers include the CARBOPOL® Ultrez series (Ultrez® 10, 20 and 21) and the ETD series (ETD 2020 and 2050) available from Lubrizol Inc.

A particularly preferred acrylate is CARBOPOL® Aqua SF-1. Said compound is a slightly cross-linked alkali-swellable acrylate copolymer that contains three structural units; one or more carboxylic acid monomers containing from 3 to 10 carbon atoms, one or more vinyl monomers and one or more mono- or polyunsaturated monomers.

Cellulose ethers.

A preferred soap bar contains 0.1 to 5% cellulose ethers. A more preferred soap bar contains 0.1 to 3% cellulose ethers. Preferred

7,035754 cellulose ethers are selected from alkyl celluloses, hydroxyalkyl celluloses and carboxyalkyl celluloses. A more preferred soap bar contains hydroxyalkyl celluloses or carboxyalkyl celluloses, and a particularly preferred soap bar contains carboxyalkyl cellulose.

Preferred hydroxyalkyl cellulose includes hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and ethyl hydroxyethyl cellulose. Preferred carboxyalkyl cellulose includes carboxymethyl cellulose. It is particularly preferred that the carboxymethyl cellulose is in the form of the sodium salt of carboxymethyl cellulose.

Wax and polyalkylene glycols.

The preferred wax includes paraffin wax and microcrystalline wax. When polyalkylene glycols are used, the preferred soap bar may contain from 0.01 to 5 wt% polyalkylene glycols, more preferably 0.03 to 3 wt%, and most preferably 0.5 to 1 wt%. Suitable examples include polyethylene glycol and polypropylene glycol. The preferred commercial product is POLYOX® sold by The Dow Chemical Company.

A preferred composition according to the present invention contains (wt%):

1) 30-85% soap, preferably sodium soap;

2) from 0.1 to 20% polyol, preferably glycerin, sorbitol, or mixtures thereof;

3) from 0.1 to 25% of particles; and

4) 10-30% water.

In the specified preferred embodiment of the present invention:

a) the ratio of C ₁₀ fatty acid to C ₁₂ fatty acid is from 0.5: 1.0 to 1.5: 1.0;

b) C1 ₄ -acid is used in an amount of not more than 3.5 wt.%;

c) oleic acid is 26-34 wt% and

d) C18 acid other than oleic acid is 0 to 8% by weight.

In a preferred embodiment of the present invention, the bar soap is prepared using a mixture of palm oil (PM), palm stearin (PS) and palm kernel oil (PMO), and the ratio (PM plus PS) to PMO is 75:25, preferably 60:40.

In a second embodiment, the present invention includes a method of improving foaming in water with a high electrolyte content, comprising applying to the skin or a suitable substrate the bar soap compositions as defined above, wherein the improvement in foaming is achieved as compared to the soap bar made from oils of the same kind taken in such the same ratios (eg, 60:40 PM plus SPM / NMR), but in which particular fatty acid mixtures are not optimized to meet the specific criteria defined by the present invention.

The increase in the amount of foam from a soap bar of the present invention (tested in water of a given hardness), measured in ml using a SITA® foam tester or in a quantitative test also defined in the protocol, is greater than about 30%, preferably more than about 40%, according to compared to bar soaps outside the scope of the present invention (eg, not optimized as defined by the present invention).

In another embodiment, the present invention relates to a method of improving foaming in water having a hardness greater than about 25 French degrees of hardness (FH) (about 5 ° F), preferably greater than about 50 French degrees of hardness (about 10 ° F), more preferably greater than about 75 FH (about 15 ° F), even more preferably greater than about 100 FH (about 20 ° F), comprising applying to the skin or other substrate the bar soap compositions of claim 1, wherein improved foaming is achieved over the soap bar made from oils the same species, taken in the same ratios, but having different C ₁₀ : C ₁₂ ratios for specific mixtures of fatty acids, minimum amounts of C ₁₄ acid and minimum amounts of unsaturated C ₁₈ acid other than oleic acid.

Protocols and examples

Foam Volume Quantification Protocol.

1. Introduction.

The amount of foam produced by a bar soap is an important parameter influencing consumer preferences. The method for determining the volume of foam, given in this application, allows you to measure the foam formation under standard conditions, thus ensuring an objective comparison of various soap formulations.

2. Principle.

The lather is obtained by qualified specialists using a standard method. The foam is collected and its volume measured.

3. Equipment.

Rinse Bowl - 1 per test taker, 10 L capacity;

Soap dishes with holes for water drainage - 1 per sample;

Rubber surgical gloves;

Tall cylindrical glass - 400 ml, 25 ml graduated (Pyrex # 1000);

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Thermometer;

Glass stick.

Test procedure.

i) Pre-treatment of soap bars.

Wearing rubber surgical gloves that have been previously washed with normal soap, wash all test bars (eg, bars) of soap at least 10 minutes before starting the test sequence. This is best done by turning these pieces 180 ° (i.e. half a turn) about 20 times under running water (about 30 ° C).

ii) Place in a bowl about 5 liters of water of known hardness and temperature. Typically, the water temperature is approximately 30 ° C and is kept constant for a given series of assessments. Change the water after testing each bar of soap.

iii) Take a bar of soap, immerse it in water and remove. Rotate the piece in your hands 180 ° 15 times. Place the piece in a soap dish.

iv) Lather is formed by soap remaining on the gloves.

Stage 1. Rub one hand against the other (both hands in the same direction) 10 times in the same way.

Stage 2. Squeeze the right hand with the left, or vice versa, and drive the foam to the fingertips.

This operation is repeated five times. Repeat steps 1 and 2. Place the foam in a glass.

v) Repeat the entire foaming procedure from point (iii) two more times with all the foam in the specified beaker.

vi) Gently stir the combined foam to release large pockets of air. Take readings and record the foam volume.

Data analysis is performed by two-way ANOVA followed by Tukey's test.

Measurement report using SITA® R2000 foaming machine (quantitative).

1. Set the parameters on the equipment as follows:

a) volume: 250 ml,

b) bath temperature: 37 ° C,

c) Measurements: 99,

d) speed: 800 rpm,

e) shaking time: 20 s.

2. Get a 10 wt.% Soap solution in a solution that simulates sea water. (The composition of the simulated seawater solution is defined in the table in Example 2 and has a French hardness of 635 FH (127 ° F)).

3. Press the power button and leave the device to work.

Foam volume qualitative assessment protocol:

- wet your hands and moisten a bar of soap;

- turn the bar of soap 15 times outside the water;

- put a bar of soap in a soap dish and collect the resulting foam;

- clasp hands 3 times and collect the resulting foam;

- rub your hands 3 times with a back and forth movement and collect the resulting foam;

- clasp hands 3 times and collect the resulting foam;

- rub your hands 3 times with a back and forth movement and collect the resulting foam;

- clasp hands 3 times and collect all the formed foam;

- to evaluate the volume of foam according to a visual scale, where, during the determination on a visual scale, it is considered that the test composition that does not form foam corresponds to the zero level, and the composition with the maximum amount of foam corresponds to the tenth level.

Examples of

A solid moisturizing personal care bar soap was prepared using various percentages of fatty acids according to the formulations described later herein.

The fatty acids used to prepare the formulations are supplied by Cosmoquimica under the trade name Edenor® C8 98/100 (caprylic acid); Edenor® C10 98/100 (capric acid); Edenor® C12 98/100 (lauric acid); Edenor® C14 98/100 (myristic acid); Edenor® C16 98/100 (palmitic acid); Edenor® C18 98/100 (stearic acid); Edenor® C18: 1 98/100 (oleic acid).

Other potential suppliers of fatty acids include Quimico Anastacio, Emery Oleochemicals and Aboissa 0leos Vegetais.

Example 1 and Comparative Examples A and B.

The different distributions of fatty acid soaps are shown in table. 1.

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Composition Comparative example A (blending traditional oils) Comparative example B (mixing traditional oils) Table 1 Example 1 (optimized mixing) C ₈ caprylic 0.92 1.53 2.00 Xiu capric 0.70 1.32 14.00 Xiu lauric 10.12 19.45 14.00 Si myristic 4.15 6.93 2.00 Cu i myristaidinic 0.00 0.00 0.00 Xiu pentadecane 0.05 0.04 0.00 Ssh palmitic 41.87 29.16 17.00 Xu.! palmitoleic 0.11 0.10 0.00 Sp margarine 0.10 0.07 0.00 CPS heptadecene 0.00 0.00 0.00 Xiu stearic 5.15 4.25 17.00 Xu.1 oleic 29.61 30.11 32.00 Xu.2 linoleic 6.89 6.73 2.00 Syu.z linolenic 0.13 0.11 0.00 C ₂ o arachidic 0.09 0.04 0.00 C20.1 gadoleic 0.00 0.00 0.00 C ₂₂ behenic 0.11 0.16 0.00 C ₂ 4 lignoceric 0.00 0.00 0.00 Others 0.00 0.00 0.00 Iodine number (r _1/2 100 g) * 39.54 39.65 32.00 Total short saturated 15.90 29.23 32.00 acids (%) Total unsaturated acids 36.74 37.05 34,00 (%) Total long saturated 47.36 33.71 34,00 acids (%)

Palm oil 40 58 - Palm oil stearin 40 2 - PYM 20 40 - (traditional (traditional (60/40 like bar soap bar soap optimized 80/20) 60/40) according to invention)

* grams of iodine per 100 g.

Assessment results ** when using sea water Comparative example A Comparative example B Example 1 Foam quantity value (ml) 50 56 238 (quantitative test) Quality scale (0-10) 0-2 0-2 8-10

** The seawater had a hardness as shown in the table below in example 2.

The results indicate that heavy foam even under extreme water conditions (for example, when the amount of mono and bivalent salts per liter of water was> 3 g / L, more than 6 g / L or more) was not obtained by increasing the amount of natural oils ( comparative example B) was used where a larger amount of palm kernel oil (PYAM), and by controlling the amount of short chain oils (oils based on C8, C _10, C _12, C ₁₄ a-acids). In particular,

10,035754 the amounts of C ₁₀ acid and C ₁₂ acid were increased (and maintained within tight ratios according to the formula of the present invention) while minimizing the amount of C ₁₄ acid and unsaturated C ₁₈ acid other than oleic acid. As indicated, in the case of the composition with a given ratio of components (example 1), the foam volume was 238 ml (compared to 50 or 56 in comparative examples A and B), and on the quality scale, qualified study participants noted values of 8-10.

Example 2.

The hardness level of sea water and water from other sources is indicated below.

table 2 Water composition 18 ° FH * (3.6 ° F) Brackish Brackish Sea water water in Africa water in india Sodium chloride Trace 1.82 3.24 24.1 quantity Magnesium chloride 0.09 1.23 0.3 5.1 Sodium sulfate 0 0 0 4.0 Calcium chloride 0.198 3.47 0.41 1.1 Potassium chloride 0 0 0 0.8 Rigidity 18 442 69 635 * FH = French degrees of hardness.

As indicated, seawater was used to obtain the results of Example 1. The example also demonstrates a high level of hardness (over 50, over 100) of brackish water in various countries.

Applicants also investigated (in seawater using the protocol for SITA®) the maximum suds for individual soaps based on fatty acids with chain lengths C ₈ , C ₁₀ , C ₁₂ , C ₁₄ ; for the composition of example 1 and the composition of comparative example B, and the results are shown below.

Table 3 Carbon chain Maximum foam volume (ml) C8 440 SJ 390 C12 440 C14 150 Ideal composition (С10-С12) 1: 1 435 Traditional soap 60/40 270

As can be seen from these data, salt water (for example, containing sodium ions) has a strong negative effect on foaming, especially on soaps based on fatty acids with a chain length of C ₁₄ . It is also clearly seen that the composition, in which the shorter chain length is optimized compared to the traditional bar soap, showed much better foaming.

Example 3.

Applicants also took the optimized formulation (Example 1) and diluted the formulations to various ratios. By the term diluted, we mean the presence of a higher amount of longer chain fatty acids from which, as can be seen, less foaming would be expected. The diluted compositions were tested under laboratory conditions and in a SITA tester and the results are shown below.

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Table 4

Qualitative scale (scale 0-10) Score (ml) (Quantitative Test) SITA Foam Tester (ml) Bar soap 80/20, but with 4 108 300 higher content of acids with a shorter chain (developed according to the invention) Developed Bar Soap 70/30 8 197 415 Designed Bar Soap nine 238 425 60/40 Traditional mix 60/40 2 56 275

As can be seen, the formulated soap bar exhibits excellent performance even when diluted to a large extent (80/20). By using more shorter chain fatty acids than conventional bar soaps, superior foaming performance is surprisingly retained.

Claims (6)

CLAIM 1. A bar soap composition for improving foaming in water with a hardness of more than about 25 g / l of water, wherein said bar soap contains: a) 30-90% soap, which is a salt of an alkali metal or alkanolammonium and a fatty acid, based on the weight of the bar soap composition, while: (i) the ratio of C ₁₀ fatty acid soap to C ₁₂ fatty acid soap is from about 0.5: 1.0 to about 1.5: 1.0; (ii) the content of fatty acid with a chain length of C ₁₄ is up to about 3.5% by weight of the bar soap composition; (iii) the amount of oleic acid is from about 25 to 35% by weight of the bar soap composition; (iv) the amount of unsaturated C ₁₈ fatty acid other than oleic acid is up to about 5% by weight of the bar soap composition; b) from about 0.1 to about 15% polyol by weight of the bar soap composition; c) from about 0.1 to 25 wt.% mineral or organic particles; d) from about 10 to 30 wt.% water. 2. The composition of claim 1, wherein the ratio of the C ₁₀ acid soap to the C _{1 2} acid soap is about 1: 1. 3. A composition according to claim 1 or 2, wherein the amount of C ₁₄ acid is from about 0.1 to about 3.0 wt%. 4. Composition according to any one of claims 1 to 3, characterized in that said polyol is selected from the group consisting of glycol, sorbitol and mixtures thereof. 5. Composition according to any one of claims 1 to 4, characterized in that the bar soap is obtained from a combination of palm oil (PM), palm stearin (PS) and palm kernel oil (PMO) and the ratio (PM and PS) to PMU is from about 60:40 to about 80:20. 6. A method of improving foaming in water with a hardness greater than about 25 g / L, comprising applying to the skin or other substrate a bar soap composition according to any one of claims 1-5.