Coloured soap bar composition comprising starch

Abstract

The present invention relates to a soap composition. It more particularly relates to a coloured soap composition comprising starch for increased translucency.

Description

[0001] COLOURED SOAP BAR COMPOSITION COMPRISING STARCH

[0002] Field of the invention

[0003] The present invention relates to a soap bar composition. It more particularly relates to an extruded coloured soap composition comprising starch.

[0004] Background of the invention

[0005] Colored soap bars have been known since ages and there has always been a constant desire to make the appearance of the soap bars more and more attractive to cater to consumer appeal. One of the ways to do so have been to add colourants. But mere adding of colourant may not be enough, so pearlizers have also been explored. It is also seen that over the period of use, soap bar may loose it shine and colour.

[0006] Therefore, there is a need for a coloured soap bar with enhanced colour and translucency.

[0007] Summary of the invention

[0008] First aspect of the present invention provides a soap bar composition comprising 10 to 80 wt% total fatty matter; 0.1 to 5 wt% electrolyte; 10 to 45 wt% water; 5.5 to 45 wt% starch; and 0.01 to 2 wt% of colourant comprising an oil dispersed pigment ; wherein translucency of the soap bar is enhanced as compared to an equivalent bar in absence of starch.

[0009] Second aspect of the present invention provides a method of enhancing the translucency of a soap bar composition, the method comprising steps of: a. saponifying a fatty matter with an alkali to produce a saponified mass, wherein 0.1 to 5 wt% of an electrolyte by weight of the soap bar composition is added during the saponification process; b. adding 5.5 to 45 wt% starch or modified starch by weight of the soap bar composition and water to obtain a saponified mass; and c. extruding the saponified mass resulting from step (b) to obtain the soap bar according to the first aspect. wherein 0.01 to 2 wt% of colourant by weight of the soap bar composition is added before or after addition of starch.

[0010] Third aspect of the present invention provides use of starch in a soap bar composition according to the first aspect, comprising a colourant to enhance the colour of the soap bar composition as compared to an equivalent soap bar composition without starch.

[0011] Detailed description of the invention

[0012] These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims. For the avoidance of doubt, any feature of one aspect of the present invention may be utilized in any other aspect of the invention. The word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of.” In other words, the listed steps or options need not be exhaustive. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se. Similarly, all percentages are weight / weight percentages unless otherwise indicated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description and claims indicating amounts of material or conditions of reaction, physical properties of materials and / or use are to be understood as modified by the word “about”. Numerical ranges expressed in the format "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also contemplated.

[0013] Throughout the specification unless otherwise specified, wt% means weight % of the total weight of soap composition of the present invention.

[0014] Various components of the composition are described in greater detail below. Soap Composition

[0015] The present invention relates to a soap composition. By a soap composition it is understood to be a composition which may be used as a soap or a composition which is used to prepare a soap. More preferably the present invention provides a soap composition which is used to prepare soap bars and more preferably extruded soap bars and furthermore preferably soap bars prepared by plough shear mixer. The soap composition of the invention is especially useful for personal cleansing.

[0016] The soap composition of the present invention provides a soap bar composition comprising 10 to 80 wt% total fatty matter; 0.1 to 5 wt% electrolyte; 10 to 45 wt% water; 5.5 to 45 wt% starch; and 0.01 to 2 wt% of colourant comprising an oil dispersed pigment; wherein translucency of the soap bar is enhanced as compared to an equivalent bar in absence of starch.

[0017] The composition of the present invention is preferably used or used to prepare a shaped solid for example a bar. The cleaning soap composition is preferably used or used to prepare a wash off product that generally has sufficient amount of surfactants included therein that it is used for cleansing the desired topical surface e.g. the whole body, the hair and scalp or the face. It is applied on the topical surface and left thereon only for a few seconds or minutes and washed off thereafter with copious amounts of water.

[0018] The soap composition may additionally comprise synthetic surfactants selected from one or more from the class of anionic, non-ionic, cationic or zwitterionic surfactants, preferably from anionic surfactants. These synthetic surfactants, as per the present invention, are included in less than 8%, preferably less than 4%, more preferably less than 1% and sometimes absent from the composition. By “absent” it is meant that there is no deliberately added synthetic surfactant in the soap composition of the present invention.

[0019] The present inventors made an extruded coloured soap bar composition comprising an organic filler such as starch and it was surprisingly found that the colour of the soap bar was richer and brighter as compared to the equivalent soap bar composition without starch.

[0020] It is preferred that in soap bar composition of the present invention the starch or its derivative is included in 5.5 to 45 wt%, more preferably 8 to 40 wt% and most preferably 10 to 35 wt% by weight of the soap bar composition.

[0021] It is preferred that in soap bar composition of the present invention the starch is native starch, pre-gelatinized starch, converted starch or its mixture.

[0022] Soap

[0023] When the Total Fatty matter (TFM) in soap composition of the present invention is for personal washing application it comprises 10 to 80 wt% total amount of soap, preferably 15 to 75 wt%, more preferably 20 to 75 wt% and most preferably 25 to 70 wt% by weight of the soap composition. When the soap composition of the invention is for laundering fabrics, it comprises from 15 wt.% to 60 wt.% fatty acid soap. Preferred aspects of such soap compositions comprise at least 20 wt.%, preferably at least 25 wt.%, still preferably at least 30 wt.% and most preferably at least 35 wt.%, but typically not more than 58 wt.%, still preferably not more than 55 wt.%, still further preferably not more than 53 wt.%, still more preferably not more than 50 wt.%, and most preferably not more than 45 wt.% TFM by weight of the soap bar composition.

[0024] The term total fatty matter is used very widely and popularly in the field of soaps and detergents. The term Total Fatty Matter, abbreviated to "TFM", is used to denote the percentage by weight of fatty acid and triglyceride residues present in the personal wash composition without taking into account the accompanying cations. For a soap having 18 carbon atoms, an accompanying sodium cation will generally amount to about 8 percent by weight. Other cations may be employed as desired, for example zinc, potassium, magnesium, alkyl ammonium and aluminium.

[0025] The term soap means salt of fatty acid. Preferably, the soap is soap of Cs to C24 fatty acids. The cation may be an alkali metal, alkaline earth metal or ammonium ion, preferably alkali metals. Preferably, the cation is selected from sodium or potassium, more preferably sodium. The soap may be saturated or unsaturated. Saturated soaps are preferred over unsaturated soaps for stability. The oil or fatty acids may be of vegetable or animal origin.

[0026] The soap may be obtained by saponification of oils, fats or fatty acids. The fats or oils generally used to make soap compositions may be selected from tallow, tallow stearins, palm oil, palm stearins, soya bean oil, fish oil, castor oil, rice bran oil, sunflower oil, coconut oil, babassu oil, and palm kernel oil. The fatty acids may be from coconut, rice bran, groundnut, tallow, palm, palm kernel, cotton seed or soyabean.

[0027] The fatty acid soaps may also be synthetically prepared (e.g. by the oxidation of petroleum or by the hydrogenation of carbon monoxide by the Fischer-Tropsch process). Resin acids, such as those present in tall oil, may also be used. Naphthenic acids may also be used.

[0028] The soap compositions of the present invention preferably include low molecular weight soaps (Cs to C14 soaps) which are generally water soluble, which are in the range of 2 to 20% by weight of the composition. It is preferred that the soap composition includes 15 to 55 wt% of the soap of C16 to C24 fatty acid, which are generally water insoluble soaps. Unsaturated fatty acid soaps preferably at 15 to 42% may also be included in the total soap content of the composition. Unsaturated soaps are preferably oleic acid soaps.

[0029] Water

[0030] The soap compositions of the present invention can hold high amount of moisture or water content. The soap compositions of the present invention have 10 to 45 wt% of water, preferably 15 to 45 wt%, more preferably 15 to 40 wt% and most preferably 18 to 38 wt% of water by weight of the soap composition. Inclusion of small amount of an electrolyte (other than soap) can influence the liquid and solid phase ratio. Increasing the electrolyte content lowers the solubility of soap thereby increasing the solid phase amount, on the other hand lowering the electrolyte levels make the bars softer.

[0031] The soap composition generally comprises electrolyte and water. Electrolytes as per this invention include compounds that substantially dissociate into ions in water. Electrolytes as per this invention are not an ionic surfactant. Suitable electrolytes for inclusion in the soap making process are alkali metal salts. Preferred electrolytes include sodium sulfate, sodium chloride, sodium citrate, potassium chloride, potassium sulfate, sodium carbonate and other mono or di or tri salts of alkaline earth metals, more preferred electrolytes are sodium chloride, sodium sulfate, potassium chloride and especially preferred electrolytes are sodium chloride and sodium sulfate and combinations thereof. For the avoidance of doubt is clarified that the electrolyte is a non-soap material. For the avoidance of doubt, it is clarified that the electrolyte is a non-soap material.

[0032] The present invention comprises an electrolyte in the range of 0.1 to 5 wt% electrolyte by weight of the extruded soap bar composition, more preferably 1 to 4 wt% and most preferably 1.5 to 3.5 wt% by weight of the soap bar composition.

[0033] Electrolytes could include Na-Chloride, Na-Sulphate, Na-Citrate, Na-Carbonate or the corresponding potassium salts.

[0034] It is most preferred that sodium sulphate and sodium chloride are used as electrolytes for the composition of the present invention.

[0035] It is preferred that sodium sulphate is present in the range of 0.1 to 6 wt% of the weight of composition, more preferably 0.5 to 5 and most preferably 0.7 to 4 wt%. It is preferred that sodium sulphate is at least 0.1 wt%, more preferably at least 0.5wt%, and most preferably at least 0.7 wt% and it is preferred that it is not more than 6wt%, more preferably not more than 5 wt%, furthermore preferably not more than 4 wt% and most preferably not more than 3.5wt% of the total weight of composition of the present invention.

[0036] It is preferred that when sodium chloride is present in the range of 0.1 to 6 wt% of the weight of composition, more preferably 0.5 to 5 and most preferably 0.7 to 4 wt%. It is preferred that sodium chloride is at least 0.1 wt%, more preferably at least 0.5wt%, and most preferably at least 0.7 wt% and it is preferred that it is not more than 6wt%, more preferably not more than 5 wt%, furthermore preferably not more than 4 wt% and most preferably not more than 3.5 wt% of the total weight of composition of the present invention.

[0037] Organic filler

[0038] It is preferred that the organic filler is a starch and preferably the starch is a native starch, pre-gelatinized starch, converted starch or its mixture.

[0039] It is preferred that the organic filler in the soap composition ranges from 5 to 45 wt%, preferably from 5.5 to 40 wt%, more preferably from 6 to 38wt%, more preferably from

[0040] 6.5 to 35 wt%, further more preferably from 7 to 34 wt%, further more preferably from

[0041] 7.5 to 33 wt%, further more preferably from 8 to 32 wt% further more preferably from 10 to 30wt% and most preferably from 10.5 to 30wt% by weight of the soap bar composition.

[0042] It is preferred that when the organic filler is starch, the starch in the soap composition ranges from 5.5 to 45 wt%, preferably from 5.5 to 40 wt%, more preferably from 6 to 38wt%, more preferably from 6.5 to 35 wt%, further more preferably from 7 to 34 wt%, further more preferably from 7.5 to 33 wt%, further more preferably from 8 to 32 wt% further more preferably from 10 to 30wt% and most preferably from 10.5 to 30wt% by weight of the soap bar composition.

[0043] Suitable starch materials include natural starch (from corn, wheat, rice, potato, tapioca and the like), pre-gelatinized starch, various physically and chemically modified starch and mixtures thereof. By the term natural starch is meant starch which has not been subject to chemical or physical modification - also known as raw or native starch. A preferred starch is natural or native starch from maize (corn), cassava, wheat, potato, rice and other natural sources of it. Raw starch with different ratio of amylase and amylopectic: e.g. maize (25% amylase); waxy maize (0%); high amylase maize (70%); potato (23%); rice (16%); sago (27%); cassava (18%); wheat (30%) and others. The raw starch can be used directly or modified during the process of making the bar composition such that the starch becomes gelatinized, either partially or fully gelantinized.

[0044] Suitable starchy materials which may be used include natural starch (from corn, wheat, rice, potato, tapioca and the like), pregelatinzed starch, various physically and chemically modified starch and mixtures thereof. By the term natural starch is meant starch which has not been subjected to chemical or physical modification - also known as raw or native starch. The raw starch can be used directly or modified during the process of making the bar composition such that the starch becomes gelatinized, either partially or fully gelatinized. Such starchy materials are commercially available e.g. FARMAL® CS 3400 (corn starch) and FARMAL® WS 4400 (corn starch; waxy unmodified).

[0045] It is preferred that the organic filler is a starch and preferably the starch is a native starch, pre-gelatinized starch, converted starch or its mixture.

[0046] Colourant

[0047] The soap bar composition of the present invention comprises a colourant in the range of 0.01 to 2 wt%, more preferably 0.08 to 2 wt% and most preferably 0.1 to 1.8wt% by weight of the soap bar composition.

[0048] The colorant is selected from the group consisting of dyes, pigments and combinations thereof.

[0049] It is preferred that the colourant should be at least 0.01 wt% , more preferably at least 0.02 wt%, further more preferably 0.05 wt% and most preferably at least 0.08 wt% by weight of the soap bar composition. The colourant of the present invention comprises an oil dispersed pigment . It is preferred that the colourant comprises the oil dispersed pigment at least 50 wt%, more preferably at least 60 wt%, further more preferably at least 70 wt%, more preferably 80 wt%, most preferably at least 90 wt% and in another preferable aspect of the present invention the colourant consist 100 wt% of an oil dispersed pigment. The pigment is preferably pre-dispersed in oil and incorporated into the soap during finishing.

[0050] The colourant could be of any colour.

[0051] Non-soap surfactant

[0052] In addition to the soap of fatty acids, preferred bars may include a non-soap surfactant, which acts as a co-surfactant and which is selected from anionic, non-ionic, zwitterionic, amphoteric and cationic surfactants.

[0053] The composition of the present invention may optionally comprise non-soap surfactants in the range of 0.1 to 20 wt%, more preferably 2 to 15 wt% and most preferably in the range of 5 to 10 wt% based on the weight of the soap bar composition.

[0054] Preferred bars include 0.0001 to 15 wt% co-surfactants based on the weight of the composition. More preferred bars include 2 to 10 wt% co-surfactant and most preferred compositions include 2.5 to 6 wt% co-surfactant by weight of the soap bar composition.

[0055] Suitable anionic surfactants include water soluble salts of organic sulphuric reaction products having in the molecular structure an alkyl radical containing from 8 to 22 carbon atoms, and a radical chosen from sulphonic acid or sulphuric acid ester radicals, and mixtures thereof.

[0056] Examples of suitable anionic surfactants are sodium and potassium alcohol sulphates, especially those obtained by sulphating the higher alcohols produced by reducing the glycerides of tallow or coconut oil; sodium and potassium alkyl benzene sulphonates such as those in which the alkyl group contains from 9 to 15 carbon atoms; sodium alkyl glyceryl ether sulphates, especially those ethers of the higher alcohols derived from tallow and coconut oil; sodium coconut oil fatty acid monoglyceride sulphates; sodium and potassium salts of sulphuric acid esters of the reaction product of one mole of a higher fatty alcohol and from 1 to 6 moles of ethylene oxide; sodium and potassium salts of alkyl phenol ethylene oxide ether sulphate with from 1 to 8 units of ethylene oxide molecule and in which the alkyl radicals contain from 4 to 14 carbon atoms; the reaction product of fatty acids esterified with isethionic acid and neutralized with sodium hydroxide where, for example, the fatty acids are derived from coconut oil and mixtures thereof. The preferred water-soluble synthetic anionic surfactants are the alkali metal (such as sodium and potassium) and alkaline earth metal (such as calcium and magnesium) salts of higher alkyl benzene sulphonates and mixtures with olefin sulphonates and higher alkyl sulphates, and the higher fatty acid monoglyceride sulphates.

[0057] Suitable nonionic surfactants can be broadly described as compounds produced by the condensation of alkylene oxide groups, which are hydrophilic in nature, with an organic hydrophobic compound which may be aliphatic or alkyl aromatic in nature.

[0058] The length of the hydrophilic or polyoxyalkylene radical which is condensed with any particular hydrophobic group can be readily adjusted to yield a water-soluble compound having the desired degree of balance between hydrophilic and hydrophobic elements. Particular examples include the condensation product of aliphatic alcohols having from 8 to 22 carbon atoms in either straight or branched chain configuration with ethylene oxide, such as a coconut oil ethylene oxide condensate having from 2 to 15 moles of ethylene oxide per mole of coconut alcohol; condensates of alkylphenols whose alkyl group contains from 6 to 12 carbon atoms with 5 to 25 moles of ethylene oxide per mole of alkylphenol; condensates of the reaction product of ethylenediamine and propylene oxide with ethylene oxide, the condensate containing from 40 to 80 percent of polyoxyethylene radicals by weight and having a molecular weight of from 5,000 to 11 ,000; tertiary amine oxides of structure R3NO, where one group R is an alkyl group of 8 to 18 carbon atoms and the others are each methyl, ethyl or hydroxyethyl groups, for instance dimethyldodecylamine oxide; tertiary phosphine oxides of structure R3PO, where one group R is an alkyl group of from 10 to 18 carbon atoms, and the others are each alkyl or hydroxyalkyl groups of 1 to 3 carbon atoms, for instance dimethyldodecylphosphine oxide; and dialkyl sulphoxides of structure R2SO where the group R is an alkyl group of from 10 to 18 carbon atoms and the other is methyl or ethyl, for instance methyltetradecyl sulphoxide; fatty acid alkylolamides; alkylene oxide condensates of fatty acid alkylolamides and alkyl mercaptans. Suitable cationic surfactants that can be incorporated are alkyl substituted quarternary ammonium halide salts e.g. bis (hydrogenated tallow) dimethylammonium chlorides, cetyltrimethyl ammonium bromide, benzalkonium chlorides and dodecylmethylpolyoxyethylene ammonium chloride and amine and imidazoline salts for e.g. primary, secondary and tertiary amine hydrochlorides and imidazoline hydrochlorides.

[0059] Suitable amphoteric surfactants are derivatives of aliphatic secondary and tertiary amines containing an alkyl group of 8 to 18 carbon atoms and an aliphatic radical substituted by an anionic water-solubilising group, for instance sodium 3- dodecylamino-propionate, sodium 3-dodecylaminopropane sulphonate and sodium N- 2-hydroxydodecyl-N- methyltaurate.

[0060] Suitable zwitterionic surfactants are derivatives of aliphatic quaternary ammonium, sulphonium and phosphonium compounds having an aliphatic radical of from 8 to 18 carbon atoms and an aliphatic radical substituted by an anionic water-solubilising group, for instance 3-(N-N-dimethyl-N- hexadecylammonium) propane-1 -sulphonate betaine, 3-(dodecylmethyl sulphonium) propane-1 -sulphonate betaine and 3- (cetylmethylphosphonium) ethane sulphonate betaine.

[0061] Further examples of suitable detergent-active compounds are compounds commonly used as surface-active agents given in the well-known textbooks "Surface Active Agents", Volume I by Schwartz and Perry and "Surface Active Agents and Detergents", Volume II by Schwartz, Perry and Berch.

[0062] Other preferred ingredients In addition to the ingredients described earlier, preferred cleansing bar may include other ingredients.

[0063] A preferred bar may include up to 30 wt% benefit agents. Preferred benefit agents are moisturizers, emollients, sunscreens and anti-ageing compounds. The agents may be added at an appropriate step during the process of making the bars. Some benefit agents may be introduced as macro domains. Examples of moisturizers and humectants include cetyl alcohol, CARBOPOL® 934, ethoxylated castor oil, paraffin oils, lanolin and its derivatives. Silicone compounds such as silicone surfactants like DC ®3225C (Dow Corning) and / or silicone emollients, silicone oil (DC-200 ® ex. Dow Corning) may also be included. Sunscreens such as 4- tertiary butyl-4'- methoxy dibenzoylmethane (available under the trade name PARSOL ® 1789 from Givaudan) or 2-ethyl hexyl methoxy cinnamate (available under the trade name PARSOL ®MCX from Givaudan) or other UV-A and UV-B sun-screens may also be added. Lipids such as cholesterol, ceramides, and pseudoceramides, and exfoliant particles such as polyethylene beads, walnut shells, apricot seeds, flower petals and seeds may also be present. Structurants such as maltodextrin or starch may be used to structure the bars. Preferred bars may also include essential oils such as bergamot and citrus or insoluble extracts of avocado, grape, grapeseed, myrrh, cucumber, watercress, calendula, elder flower, geranium, linden blossom, amaranth, seaweed, gingko, ginseng and other plant extracts. Further optional ingredients include chelating agents such as ethylene diamine tetra acetic acid, preservatives (e.g. GLYDANT ®) antioxidants, and natural and synthetic perfumes. Cationic polymers may be included as conditioners. These include POLYQUATERNIUM ® , MERQUAT ® polymers, and JAGUAR ® polymers. The composition can also optionally include other ingredients conventionally used in soap such as lather boosters, hemectants such as glycerine, moisturisers, colourants and opacifiers.

[0064] Other adjunct materials may include germicides and preservatives. These ingredients normally will be in amounts less than 2 wt%, usually less than 0.5 wt%. Other optional ingredients like anti-oxidants, perfumes, polymers, chelating agents, colourants, deodorants, dyes, emollients, moisturizers, enzymes, foam boosters, germicides, antimicrobials, lathering agents, pearlescers, skin conditioners, stabilisers, superfatting agents, sunscreens may be added in suitable amounts in the process of the invention. Preferably, the ingredients are added after the saponification step and before filtering. Sodium metabisulphite, ethylene diamine tetra acetic acid (EDTA), borax and ethylene hydroxy diphosphonic acid (EHDP) are preferably added to the formulation.

[0065] It is preferred that the cleansing bar has no or essentially no opacifiers. By opacifiers is meant compounds which limit the quantity of light passing through the solid composition. When opacifiers are present, the solid composition is generally opaque, i.e. "opacification". Examples of opacifiers include titanium dioxide, zinc oxide and the like.

[0066] The soaps bar composition may optionally comprise 0.1 to 15%, preferably 0.2 to 12% by weight of free fatty acids. By free fatty acids is meant a carboxylic acid comprising a hydrocarbon chain and a terminal carboxyl group bonded to an H. Suitable fatty acids are C8 to C22 fatty acids. Preferred fatty acids are C12 to C18, preferably predominantly saturated, straight-chain fatty acids. However, some unsaturated fatty acids can also be employed.

[0067] The composition preferably comprises a polyhydric alcohol (also called polyol) or mixture of polyols. Polyol is a term used herein to designate a compound having multiple hydroxyl groups (at least two, preferably at least three) which is highly water soluble. 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, manitol, sucrose and glucose; modified carbohydrates such as hydrolyzed starch, dextrin and maltodextrin, and polymeric synthetic polyols such as polyalkylene glycols, for example polyoxyethylene glycol (PEG) and polyoxypropylene glycol (PPG). Especially preferred polyols are glycerol, sorbitol and their mixtures. Most preferred polyol is glycerol. In a preferred embodiment, the bars of the invention comprise 0 to 8%, preferably 1 to 7.5% by wt. polyol.

[0068] The various optional ingredients that make up the final soap composition are as described below:

[0069] The total level of the adjuvant materials used in the bar composition generally is in an amount not higher than 50%, preferably 1 to 50%, more preferably 3 to 45% by wt. of the soap composition.

[0070] The adjuvant system may optionally include insoluble particles comprising one or a combination of materials. By insoluble particles is meant materials that are present in solid particulate form and suitable for personal washing. Preferably, there are mineral (e.g., inorganic) or organic particles.

[0071] The insoluble particles should not be perceived as scratchy or granular and thus should have a particle size less than 300 microns, more preferably less than 100 microns and most preferably less than 50 microns.

[0072] Preferred inorganic particulate material may be inorganic fillers, including but not limited to talc, clay and calcium carbonate. Talc is a magnesium silicate mineral material, with a sheet silicate structure and a composition of Mg3Si4(OH)22 and may be available in the hydrated form. It has a plate-like morphology, and is essentially oleophilic / hydrophobic, i.e., it is wetted by oil rather than water.

[0073] Calcium carbonate or chalk exists in three crystal forms: calcite, aragonite and vaterite. The natural morphology of calcite is rhombohedral or cuboidal, acicular or dendritic for aragonite and spheroidal for vaterite.

[0074] Examples of other optional insoluble inorganic particulate materials include aluminates, silicates, phosphates, insoluble sulfates, borates and clays (e.g., kaolin, china clay) and their combinations.

[0075] Organic particulate materials include: insoluble polysaccharides such as highly crosslinked or insolubilized starch (e.g., by reaction with a hydrophobe such as Octyl succinate) and cellulose; synthetic polymers such as various polymer lattices and suspension polymers; insoluble soaps and mixtures thereof.

[0076] It is preferred that the compositions of the invention comprise polymers. Polymers of the acrylate class are especially preferred. Preferred bars include 0.05 to 5% acrylates. More preferred bars include 0.01 to 3% acrylates. Examples of acrylate polymers include polymers and copolymers of acrylic acid crosslinked with polyallylsucrose as described in US Patent 2,798,053 which is herein incorporated by reference. Other examples include polyacrylates, acrylate copolymers or alkali swellable emulsion acrylate copolymers, hydrophobically modified alkali swellable copolymers, and crosslinked homopolymers of acrylic acid. Examples of such commercially available polymers are: ACLILYN®, CARBOPOL®, and CARBOPOL® Ultrez grade series.

[0077] Bar compositions preferably comprise 0.1 to 25% by wt. of bar composition, preferably 5 to 15 by wt. of these mineral or organic particles.

[0078] An opacifier may be optionally present in the personal care composition. When opacifiers are present, the cleansing bar is generally opaque. Examples of opacifiers include titanium dioxide, zinc oxide and the like. A particularly preferred opacifier that can be employed when an opaque soap composition is desired is ethylene glycol mono- or di-stearate, for example in the form of a 20% solution in sodium lauryl ether sulphate. An alternative opacifying agent is zinc stearate.

[0079] The product can take the form of a water-clear, i.e. transparent soap, in which case it will not contain an opacifier.

[0080] In the soap composition of the present invention the composition has a pH when measured in a 4% solution with distilled water at 25°C in the range from 9 to 13.

[0081] A preferred bar may additionally include up to 30 wt% benefit agents. Preferred benefit agents include moisturizers, emollients, sunscreens and anti-ageing compounds. The agents may be added at an appropriate step during the process of making the bars. Some benefit agents may be introduced as macro domains.

[0082] Other optional ingredients like anti-oxidants, perfumes, polymers, chelating agents, colourants, deodorants, dyes, enzymes, foam boosters, germicides, anti-microbials, lathering agents, pearlescers, skin conditioners, stabilizers or superfatting agents, may be added in suitable amounts in the process of the invention. Preferably, the ingredients are added after the saponification step. Sodium metabisulphite, ethylene diamine tetra acetic acid (EDTA), borax or ethylene hydroxy diphosphonic acid (EHDP) are preferably added to the formulation.

[0083] The composition of the invention could be used to deliver antimicrobial benefits. Antimicrobial agents that are preferably included to deliver this benefit include oligodynamic metals or compounds thereof. Preferred metals are silver, copper, zinc, gold or aluminium. Silver is particularly preferred. In the ionic form it may exist as a salt or any compound in any applicable oxidation state. Preferred silver compounds are silver oxide, silver nitrate, silver acetate, silver sulfate, silver benzoate, silver salicylate, silver carbonate, silver citrate or silver phosphate, with silver oxide, silver sulfate and silver citrate being of particular interest in one or more embodiments. In at least one preferred embodiment the silver compound is silver oxide. Oligodynamic metal or a compound thereof is preferably included in 0.0001 to 2%, preferably 0.001 to 1% by weight of the composition. Alternately an essential oil antimicrobial active may be included in the composition of the invention. Preferred essential oil actives which may be included are terpineol, thymol, carvacol, (E) -2(prop-1-enyl) phenol, 2- propylphenol, 4- pentylphenol, 4-sec-butylphenol, 2-benzyl phenol, eugenol or combinations thereof. Furthermore, preferred essential oil actives are terpineol, thymol, carvacrol or thymol, most preferred being terpineol or thymol and ideally a combination of the two. Essential oil actives are preferably included in 0.001 to 1%, preferably 0.01 to 0.5% by weight of the composition.

[0084] In soap compositions for laundering fabric, one or more of the above described optional ingredients may be included. However, in laundry bars, antimicrobial agents are generally not added. Laundry bars generally include chelating agents that are generally not included in soap compositions for personal cleansing. Chelating agents may be selected from but not limited to ethylene diamine tetra acetic acid (EDTA), ethylene hydroxy diphosphonic acid (EHDP) or mixtures thereof. The chelating agent is preferably present in an amount ranging from 0.01 wt.% to 1 wt.%. Non-phosphate chelating agents like methylglycinediacetic acid and salts thereof are also preferred.

[0085] Process

[0086] In a second aspect, the present invention relates to method of enhancing the translucency of a soap bar composition, the method comprising steps of: a. saponifying a fatty matter with an alkali to produce a saponified mass, wherein 0.1 to 5 wt% of an electrolyte by weight of the soap bar composition is added during the saponification process; b. adding 5.5 to 45 wt% starch or modified starch by weight of the soap bar composition and water to obtain a saponified mass; and c. extruding the saponified mass resulting from step (b) to obtain the soap bar according to the first aspect. wherein 0.01 to 2 wt% of colourant by weight of the soap bar composition is added before or after addition of starch.

[0087] The soap composition may be made into a bar by a press that first involves saponification of the fat charge with alkali followed by extruding the mixture in a conventional plodder. The plodded mass may then be optionally cut to a desired size and stamped with a desirable indicia. An especially important benefit of the present invention is that, notwithstanding the high amount of water content of the soap composition, compositions thus prepared by extrusion are found to be easy to stamp with a desirable indicia. By “easy to extrude” is meant that the hardness of the bar as it is extruded is high enough that it exits the extruder in a firm enough form that it can be called a rigid bar. The hardness of the bar is preferably higher than 1.2 kg, more preferably in the range of 1.2 to 5.0 kg (at 40°C). The hardness is preferably measured using the TA-XT Express apparatus available from Stable Micro Systems. The hardness is measured using this apparatus with a 30° conical probe - Part #P / 30c to a penetration of 15 mm. If the soap mass is too soft and is passed through the extruder it will not extrude out of the extruder in a cohesive enough mass to be called a bar. By “easy to stamp” is meant that the soap composition is of such a consistency and low enough stickiness that it does not stick to the die that is used to stamp any desired indicia on the bar. The soap composition prepared by the process of the invention therefore preferably comprises an indicium stamped thereupon.

[0088] The specific process that may be employed using the above described general process for soap composition manufacture comprises one of the following processes.

[0089] It is preferred that in the process of the present invention the TFM of soap composition is in the range of 10 to 80% by weight of the soap bar composition.

[0090] It is preferred that in the process of the present invention the soap composition comprises 10 to 45 wt% water by weight of the soap bar composition. It is preferred that in the process of the present invention the soap composition comprises 0.1 to 5 wt% of an electrolyte by weight of the soap bar composition.

[0091] It is preferred that in the process of the present invention the soap composition, the colourant comprises an oil dispersed pigment and most preferably the colourant is in the range of 0.01 to 2 wt% by weight of the soap bar composition.

[0092] It is preferred that the soap composition of the present invention is prepared in a plough shear mixer.

[0093] Use

[0094] The present invention provides use of starch in a soap bar composition according to the first aspect, comprising a colourant to enhance the colour of the soap bar composition as compared to an equivalent soap bar composition without starch.

[0095] The present invention provides use of starch in a soap bar composition according to the first aspect, wherein starch or its derivative is 5 to 45 wt% by weight of the soap bar composition.

[0096] The present invention provides use of starch in a soap bar composition according to the first aspect, wherein starch or its derivative is 10 to 35 wt% by weight of the soap bar composition.

[0097] The present invention provides use of starch in a soap bar composition according to the first aspect, wherein the starch is native starch, pre-gelatinized starch, converted starch or its mixture.

[0098] The present invention provides use of starch in a soap bar composition according to the first aspect, claimed in any one of the preceding claims wherein the soap bar composition comprises 10 to 80 wt% total fatty matter by weight of the soap bar composition. The present invention provides use of starch in a soap bar composition according to the first aspect, wherein the soap bar composition comprises 0.1 to 5 wt% electrolyte by weight of the soap bar composition.

[0099] The present invention provides use of starch in a soap bar composition according to the first aspect, wherein the soap bar composition comprises 10 to 45 wt% of water by weight of the soap bar composition.

[0100] It is preferred that in the use of the present invention the soap composition, the organic filler is starch and is present in the range of 5.5 to 45wt% by weight of the soap bar composition.

[0101] It is preferred that in the use of the present invention the soap composition, the colourant comprises an oil dispersed pigment and most preferably the colourant is in the range of 0.01 to 2 wt% by weight of the soap bar composition.

[0102] It is preferred that in the use of the present invention is prepared in a plough shear mixer.

[0103] EXAMPLES

[0104] Example 1- Soap Bars

[0105] The soap bars were prepared in accordance with the soap compositions of the present invention as mentioned in Table 1.

[0106] The fatty acids / fats according to the required blend was weighed and neutralized using sodium hydroxide. The electrolytes sodium sulphate and sodium chloride were added during saponification process. Then, the saponified soap mass was converted into noodle by passing through child drum and noodler. The noodles were converted into soap bar by adding SLS, starch, minors, perfumes etc into sigma mixer than plodding through an extruder. Colorant is pigment is pre-dispersed in oil and incorporated into the soap during finishing, it can be added optionally in sigma mixture stage before or after starch addition. The soap bars were prepared in accordance with the soap compositions of the present invention. For measurement of translucency Lux meter, Model No - Fluke 941 Light Meter was used. The experiment was set up with one closed box with Lux meter and 17 W LED bulb was used as a light source. The Fluke 941 measures the visible light from fluorescent, metal halide, high pressure sodium or incandescent sources. One LUX (Lumen) is the illumination from a one candela lamp perpendicular to a surface one meter squared at a distance of one meter. One foot-candle (Fc) is the illumination from a one candela lamp perpendicular to a surface one foot squared at a distance of one foot. Distance between light source and soap top surface was kept to be about 35 mm. Distance between soap bottom surface and Lux meter was kept about -100 mm. And readings were taken Table 1 Therefore, it is clearly evident from the data of table 1 that there is a vast difference in the translucency exhibited by a soap bar when starch is used as compared to a similar control composition without starch.

Claims

Claims1. An extruded soap bar composition comprising: i. 10 to 80 wt% total fatty matter ; ii. 0.1 to 5 wt% electrolyte; iii. 10 to 45 wt% water; iv. 5.5 to 45 wt% starch; and v. 0.01 to 2 wt% colourant comprising an oil dispersed pigment.

2. A soap bar composition according to claim 1 , wherein the starch is included in 8 to 35 wt% by weight of the soap bar composition.

3. A soap bar composition according to claims 1 or 2, wherein the starch is native starch, pre-gelatinized starch, converted starch or its mixture.

4. A soap bar composition according to anyone of the preceding claims from 1 to3, wherein the soap bar composition comprises 20 to 75 wt% total fatty matter by weight of the soap bar composition.

5. A soap bar composition according to anyone of the preceding claims from 1 to4, wherein the soap bar composition comprises 1 to 4 wt% electrolyte by weight of the soap bar composition.

6. A soap bar composition according to anyone of the preceding claims from 1 to5, wherein the soap bar composition comprises 15 to 45 wt% of water by weight of the soap bar composition.

7. A method of enhancing the translucency of a soap bar composition, the method comprising steps of: a. saponifying a fatty matter with an alkali to produce a saponified mass, wherein 0.1 to 5 wt% of an electrolyte by weight of the soap bar composition is added during the saponification process;b. adding 5.5 to 45 wt% starch or modified starch by weight of the soap bar composition and water to obtain a soap mass; and c. extruding the soap mass resulting from step (b) to obtain the soap bar according to any one of claims 1 to 6. wherein 0.01 to 2 wt% of colourant by weight of the soap bar composition is added before or after addition of starch.

8. Use of starch in an extruded soap bar composition comprising: i. 10 to 80 wt% total fatty matter ; ii. 0.1 to 5 wt% electrolyte; iii. 10 to 45 wt% water; iv. 0.01 to 2 wt% colourant comprising an oil dispersed pigment ; to enhance the translucency of the soap bar composition as compared to an equivalent soap bar composition without starch.

9. Use of starch in a soap bar composition according to claims 6, wherein starch is 5.5 to 45 wt% by weight of the soap bar composition.

10. Use according to anyone of preceding claims from 7 to 9, wherein starch is 8 to 35 wt% by weight of the soap bar composition.

11. Use according to anyone of preceding claims from 7 to 10, wherein the starch is native starch, pre-gelatinized starch, converted starch or its mixture.

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