XANTHAN STRUCTURED HIGH POLYOL LIQUID CLEANSERS

Abstract

The invention relates to high polyol compositions comprising foaming, preferably mild surfactants. While xanthan gum is normally incompatible with such composition, applicants have surprisingly found compositions (having specified particles size) and process for making such compositions such that xanthan gum can now be used as structurant.

Claims

1. A composition comprising: a) 40% to 75% by wt. polyol; b) 1% to 15% of a surfactant selected from the group consisting of anionic surfactants, non-ionic surfactants, amphoteric surfactants, zwitterionic surfactants, cationic surfactants and mixtures thereof; c) 0.1% to 1.5% by wt. xanthan gum; d) 10% to 50% water; and e) wherein viscosity of final composition is 2000 to 15,000 cps as measured using #5 spindle at 20 rpm for 30 seconds.

2. A composition according to claim 1 wherein said surfactant comprises a surfactant selected from the group consisting of salts of N-acyl derivatives of dicarboxylic, or salts of N-acyl derivatives of moncarboxylic acid and mixtures thereof.

3. A composition according to claim 1, wherein polyol is glycerin.

4. A composition according to claim 1 wherein xanthan gum is in the form of particles having a size of 50 microns or less.

5. A process for making a composition comprising: a) 40% to 75% by wt. polyol; b) 1% to 15% of a surfactant selected from the group consisting of anionic surfactants, non-ionic surfactants, amphoteric surfactants, zwitterionic surfactants, cationic surfactants and mixtures thereof; c) 0.1% to 1.5% by wt. xanthan gum; d) 10% to 50% water; and e) wherein viscosity of final composition is 2000 to 15,000 cps as measured using #5 spindle at 20 rpm for 30 seconds wherein said process comprises: 1) adding and mixing all xanthan gum with 5 to 10 parts of polyol to form a uniform mixture; 2) separately adding and mixing balance of polyol, surfactant and water in a separate mixer; 3) adding the xanthan gum in polyol mixture of (1) to the mixture of (2) and homogenizing the mixture of (1) and (2) with suitable homogenization such that xanthan particles in final mix have size of 50 microns or less.

6. A process according to claim 5, wherein homogenization is with a rotor-stator mixer and is conducted at homogenization speed greater than 500 rpm for four minutes or greater.

7. A process according to claim 5 wherein surfactant of (2) comprises a surfactant selected from the group consisting of salts of N-acyl derivatives of dicarboxylic, or salts of N-acyl derivatives of moncarboxylic acid and mixtures thereof.

8. A process according to claim 5, wherein polyol is glycerin.

9. A process for making a composition comprising: a) 40 to 75% by wt. polyol; b) 1 to 15% by wt. of a surfactant selected from the group consisting of anionic surfactants, non-ionic surfactants, amphoteric surfactants, zwitterionic surfactants, cationic surfactants and mixtures thereof; c) 0.1% to 1.5% by wt. xanthan gum; d) 10% to 50% water; and e) wherein viscosity of final composition is 2000 to 15,000 cps as measured using #5 spindle at 20 rpm for 30 seconds. wherein said process comprises: 1) premixing 4 to 8 wt % of xanthan gum with 10 to 20 wt % of polyol; 2) adding and mixing the xanthan and polyol mixture to 75 to 90 wt % surfactant solution with total surfactant level being higher than 15 wt %, preferably higher than 20%; 3) homogenizing the predispersion of (1) plus (2) under homogenization conditions sufficient to obtain xanthan particles of 50 microns or less; and 4) adding and mixing the xanthan gum predispersion of (3) to a mixer containing the rest of the ingredients, said mixing being for over 5 minutes.

10. A process according to claim 9 wherein homogenization is with a rotor-stator mixer and is conducted at homogenization speed greater than 500 rpm for four minutes or greater.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0041] Except in the examples, or where otherwise explicitly indicated, all numbers in this description 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. All amounts are by weight of the final composition, unless otherwise specified.

[0042] It should be noted that in specifying any range of concentration or amount, any particular upper concentration can be associated with any particular lower concentration or amount.

[0043] For the avoidance of doubt, 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.

[0044] The disclosure of the invention as found herein is to be considered to cover all embodiments as found in the claims as being multiply dependent upon each other irrespective of the fact that claims may be found without multiple dependency or redundancy.

[0045] The present invention provides compositions comprising high levels of polyol, preferably glycerine, in which xanthan gum surprisingly can be used as a structurant and provide good viscosity. Specifically, applicants have found that, by preparing in a particular manner (using homogenization), novel compositions can be obtained.

[0046] More particularly, novel compositions of the invention comprise: [0047] 1) 40% to 75%, preferably 45% to 75%, more preferably 50 to 75% by wt. polyol (preferably glycerine); [0048] 2) 1% to 15% of a surfactant selected from the group consisting of anionic surfactants, non-ionic surfactants, amphoteric surfactants, zwitterionic surfactants, cationic surfactants and mixtures thereof; salts of N-acyl derivatives of dicarboxylic amino acid (e.g., aspartic acid, glutamic acid) or salts of N-acyl derivatives of monocarboxylic acids (e.g., glycine alamine) and derivatives are particularly preferred; [0049] 3) 0.1% to 1.5%, preferably 0.3% to 1.2% xanthan gum; [0050] 4) 10% to 50% water; and [0051] 5) wherein viscosity of final composition is 2000 to 15,000 cps, preferably 3000 to 10,000 cps, as measured using #5 spindle at 20 rpm for 30 seconds.

[0052] Preferably, the xanthan gum particles have a size of 50 microns or less, preferably 0.1 to 50 microns, preferably 0.5 to 40 microns.

[0053] Compositions of the invention comprise, as noted, 40 to 75%, preferably 45 to 75% polyol. While glycerine is preferred polyol, other polyols may be used. These include sorbitol, propylene glycol, polypropylene glycol and mixtures thereof (including preferably, mixtures of one of these with glycerine).

[0054] The lower level of polyol used may be 40 or 45 or 50% (and all digits between) and is preferably 51% and higher, including 51 to 60 and all digits between. The upper range may be 60 to 75 and all digits in between. Of course, any digit between 41 and 74 can theoretically be upper or lower limit. For example, 74% can be the lower limit and 75% can be the upper limit.

[0055] It is unexpected that xanthan gum would be compatible with such high polyol systems. However, applicants have further discovered a process which permits such compositions while maintaining excellent viscosity. It is not recognized that xanthan needs to be homogenized (by which we mean broken down, whether in a rotor-stator mechanical mixer using rpm; or in a classic homogenizer using pressure through an inlet to homogenize) to small particle size to obtain the noted compatibility.

Surfactant

[0056] The composition may further comprise 1 to 15%, preferably 2 to 12%, even more preferably 2 to 9% by wt. surfactant selected from the group consisting of anionoic surfactants, non-ionic surfactants, amphoteric surfactants, zwitterionic surfactants, cationic surfactants and mixtures thereof.

[0057] The anionic detergent active which may be used in the invention may be aliphatic sulfonates, such as a primary alkane (e.g., C.sub.8-C.sub.12) sulfonate, primary alkane (e.g., C.sub.8-C.sub.22 disulfonate, C.sub.8-C.sub.22 alkene sulfonate, C.sub.8-C.sub.22 hydroxyalkane sulfonate or alkyl glyceryl ether sulfonate (AGS); or aromatic sulfonates such as alkyl benzene sulfonate. The anionic may also be an alkyl sulfate (e.g., C.sub.12-C.sub.18 alkyl sulfate) or alkyl ether sulfate (including alkyl glyceryl ether sulfates).

[0058] Solubilizing cation may include sodium, potassium, ammonium or substituted ammonium. Ammonium and sodium lauryl ether sulfates are preferred. The anionic may also be alkyl sulfosuccinates (including mono- and dialkyl, e.g., C.sub.6-C.sub.22 sulfosuccinates); alkyl and acyl taurates, alkyl and acyl sarcosinates, sulfoacetates, C.sub.8-C.sub.22 alkyl phosphates and phosphates, alkyl phosphate esters and alkoxyl alkyl phosphate esters, acyl lactates, C.sub.8-C.sub.22 monoalkyl succinates and maleates, sulphoacetates, alkyl glucosides and acyl isethionates, and the like. Sulfosuccinates may be monoalkyl sulfosuccinates having the formula:

R.sup.4O.sub.2CCH.sub.2CH(SO.sub.3M)CO.sub.2M; and

amide-MEA sulfosuccinates of the formula;

R.sup.4CONHCH.sub.2CH.sub.2O.sub.2CCH.sub.2CH(SO.sub.3M)CO.sub.2M

wherein R.sup.4 ranges from C.sub.8-C.sub.22 alkyl and M is a solubilizing cation.

[0059] Sarcosinates are generally indicated by the formula:

R.sup.1CON(CH.sub.3)CH.sub.2CO.sub.2M,

wherein R.sup.1 ranges from C.sub.8-C.sub.20 alkyl and M is a solubilizing cation.

[0060] Taurates are generally identified by formula:

R.sup.2CONR.sup.3CH.sub.2CH.sub.2SO.sub.3M

wherein R.sup.2 ranges from C.sub.8-C.sub.20 alkyl, R.sup.3 ranges from C.sub.1-C.sub.4 alkyl and M is a solubilizing cation.

[0061] The inventive cleansing composition may contain C.sub.8-C.sub.18 acyl isethionates. These esters are prepared by reaction between alkali metal isethionate with mixed aliphatic fatty acids having from 6 to 18 carbon atoms and an iodine value of less than 20. At least 75% of the mixed fatty acids have from 12 to 18 carbon atoms and up to 25% have from 6 to 10 carbon atoms. The acyl isethionate may be an alkoxylated isethionate such as is described in Ilardi et al., U.S. Pat. No. 5,393,466, titled Fatty Acid Esters of Polyalkoxylated isethonic acid; issued Feb. 28, 1995; hereby incorporated by reference. This compound has the general formula:

RCO(O)C(X)HC(Y)H.sub.2(OCHCH.sub.2).sub.mSO.sub.3M.sup.+

wherein R is an alky I group having 8 to 18 carbons, m is an integer from 1 to 4, X and Y are hydrogen or an alkyl group having 1 to 4 carbons and M is a monovalent cation such as, for example, sodium, potassium or ammonium.

Amphoteric Surfactants

[0062] One or more amphoteric surfactants are used in this invention. Such surfactants include at least one acid group. This may be a carboxylic or a sulphonic acid group. They include quaternary nitrogen and therefore are quaternary amido acids. They should generally include an alkyl or alkenyl group of 7 to 18 carbon atoms. They will usually comply with an overall structural formula:

R.sup.1[C(O)N H(CH.sub.2).sub.n].sub.mN(R.sup.2)(R.sup.3)XY

[0063] where R.sup.1 is alkyl or alkenyl of 7 to 18 carbon atoms;

[0064] R.sup.2 and R.sup.3 are each independently alkyl, hydroxyalkyl or carboxyalkyl of 1 to 3 carbon atoms;

[0065] n is 2 to 4;

[0066] m is 0 to 1;

[0067] X is alkylene of 1 to 3 carbon atoms optionally substituted with hydroxyl,

Y is CO.sub.2 or SO.sub.3

[0068] Suitable amphoteric surfactants within the above general formula include simple betaines of formula:

R.sup.1N.sup.+(R.sup.2)(R.sup.3)CH.sub.2CO.sub.2

and amido betaines of formula:

R.sup.1CONH(CH.sub.2).sub.nN.sup.+(R.sup.2)(R.sup.3)CH.sub.2CO.sub.2

wherein n is 2 or 3.

[0069] In both formulae R.sup.1, R.sup.2 and R.sup.3 are as defined previously. R.sup.1 may in particular be a mixture of C.sub.12 and C.sub.14 alkyl groups derived from coconut oil so that at least half, preferably at least three quarters of the groups R.sup.1 have 10 to 14 carbon atoms. R.sup.2 and R.sup.3 are preferably methyl.

[0070] A further possibility is that the amphoteric detergent is a sulphobetaine of formula:

R.sup.1N.sup.+(R.sup.2)(R.sup.3)(CH.sub.2)SO.sub.3

or

R.sup.1CON H(CH.sub.z).sub.mN+(R.sup.2)(R.sup.3)(CH.sub.2)SO.sub.3

where m is 2 or 3, or variants of these in which (CH.sub.2).sub.3SO.sub.3 is replaced by

CH.sub.2C(OH)(H)CH.sub.2SO.sub.3

[0071] In these formulae R.sup.1, R.sup.2 and R.sup.3 are as discussed previously.

[0072] Amphoacetates and diamphoacetates are also intended to be covered in possible zwitterionic and/or amphoteric compounds which may be used such as e.g., sodium lauroamphoacetate, sodium cocoamphoacetate, and blends thereof, and the like.

Nonionic Surfactants

[0073] One or more nonionic surfactants may be used in the cleansing composition of the present invention. The nonionics which may be used include in particular the reaction products of compounds having a hydrophobic group and a reactive hydrogen atom, for example aliphatic alcohols, acids, amides or alkylphenols with alkylene oxides, especially ethylene oxide either alone or with propylene oxide. Specific nonionic detergent compounds are alkyl (C.sub.6-C.sub.22) phenols ethylene oxide condensates, the condensation products of aliphatic (C.sub.8-C.sub.18) primary or secondary linear or branched alcohols with ethylene oxide, and products made 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 sulphoxide, and the like.

[0074] In some forms, the compositions of the invention may comprise a surfactant selected from the group consisting of salts of N-acyl derivatives of dicarboxylic amino acid (e.g., asparatic acid, glutamic acids), salts of N-acyl derivatives of monocarboxylic acids (e.g., glycine, alanine, sarcosine) and mixtures of such derivatives of mono- and dicarboxylic acids; Preferred di-carboxylic amino acid surfactants are acylglutamate and acylaspartate surfactants. Preferred mono-carboxylic amino acid surfactants are acylglycinate, acylalanate, and acyl sarcosinate. Preferably, these are potassium and/or sodium salts of N-acyl derivatives of amino acids.

[0075] There are typically two formats of amino acid surfactants commercially available. One is powder or flake format, which is typically more expensive and high in purity. Examples of solid dicarboxylic amino acid surfactants include: [0076] sodium N-cocoyl-L-glutamate (e.g., Amisoft CS-11 by Ajinomoto) [0077] sodium N-lauroyl-L-glutamate (e.g., Amisoft LS-11 by Ajinomoto) [0078] sodium N-myristoyl-L-glutamate (Amisoft MS-11 by Ajinomoto) [0079] potassium N-cocoyl_l-Glutamate (e.g., Amisoft CK-11 by Ajinomoto) [0080] potassium N-myristoyl-L-glutamate (Amisoft MK-11 by Ajinomoto) [0081] potassium N-lauroyl-L-glutamate (Amisoft LK-11 by Ajinomoto) [0082] Sodium Lauroyl Aspartate (AminoFoamer FLMS-P1 by Asahi Kasei Chemical Corporation) [0083] Sodium Lauroyl Glutamate (Aminosurfact ALMS-P1/S1 by Asahi Kasei Chemical Corporation) [0084] Sodium Myristoyl Glutamate (Aminosurfact AMMS-P1/S1 by Asahi Kasei Chemical Corporation)

[0085] Examples of solid monocarboxylic amino acids surfactants include: [0086] sodium cocoyl glycinate (e.g., Amilite GCS-11 by Ajinomoto) [0087] potassium cocoyl glycinate (e.g., Amilite GCK-11 by Ajinomoto

[0088] Preferably the N-acyl amino acid surfactant derivatives comprise 50 to 100% of total surfactant system.

[0089] The compositions further comprise 0.1 to 1.5% by wt., preferably 0.3% to 1.2% by wt. xanthan gum. Xanthan gums are polysaccharides which can be synthesized by fermentation of certain sugars by microorganisms such as the bacterium Xanthomonas campestris. Xanthan consists of repeating pentasaccharide units consisting of two D-glucopyranosyl units, two D-mannopyranosyl units, and one D-glucopyranosyluronic acid unit with molecular weight of from 1 million to 50 million. Xanthan gums have been widely used to thicken or stabilize aqueous system due to its excellent compatibility with many chemicals such as salts, acids, bases and water-mixable solvents. Xanthan gums preferred for the invention are commercial products, such as Keltrol CG-T, Keltrol CG-SFT or Keltrol-CG manufactured by Kelco, Vangan NF-C available from Vanderbilt and Minerals.Rhodopol 23 C from Solvay

[0090] As indicated, xanthan would not normally be incorporated as a structurant in high polyol systems especially together with surfactants as claimed in this invention. However, because of the novel processing step of our invention, applicants can make high polyol and xanthan gum systems which permits xanthan to enhance viscosity of personal liquid cleanser as claimed. The key is the recognition that xanthan gum particles must have size of 50 microns or less to ensure compatibility in such high polyol systems.

[0091] The composition further comprises 10 to 50%, preferably 15 to 40% water.

[0092] In a second form, the invention comprises a process which permits novel compositions of the invention to be made.

[0093] Specifically, this invention relates to homogenization process (as noted earlier, homogenization refers to both breaking up by rotor-stator mechanical device used at certain rpm and/or by classic homogenizer which is based on pressure feeding) for making a composition comprising: [0094] 1) 40% to 75%, preferably 45% to 75%, more preferably 50 to 75% by wt. polyol (preferably glycerine); [0095] 2) 1% to 15% of a surfactant selected from the group consisting of anionic surfactants, non-ionic surfactants, amphoteric surfactants, zwitterionic surfactants, cationic surfactants and mixtures thereof; salts of N-acyl derivatives of dicarboxylic amino acid (e.g., aspartic acid, glutamic acid) or salts of N-acyl derivatives of monocarboxylic acids (e.g., glycine alamine) and mixtures of such derivatives are particularly preferred; [0096] 3) 0.1% to 1.5%, preferably 0.3% to 1.2% xanthan gum; [0097] 4) 10% to 50% water; and

[0098] wherein viscosity of final composition is 2000 to 15,000 cps, preferably 3000 to 10,000 cps, as measured using #5 spindle at 20 rpm for 30 seconds; wherein preferably xanthan gum particles have size of 0.1 to 50 microns or 0.5 to 40 microns; and

[0099] wherein, if present, the N-acyl amino acid surfactants preferably comprise the majority of the surfactant system, e.g., 50% to 100% of the surfactant system, or 60% to 100%, or 70% to 10% of the surfactant system.

[0100] wherein said process comprises: [0101] 1) adding and mixing all xanthan gum with 5 to 10 parts of polyol (preferably glycerin) to form a uniform mixture; [0102] 2) separately adding and mixing balance of polyol, surfactant and water in separate mixer (e.g., main mixer); [0103] 3) adding xanthan gum in polyol mixture of (1) to the mixture of (2) and homogenizing the mixture of (1) and (2) with suitable homogenization such that xanthan particles in final mix have size of 50 microns or less, preferably 0.5 to 40 microns.

[0104] A homogenizer which may be used is a rotor-stator mechanical homogenizer at ahomogenization speed greater than 500 rpm, preferably 1500 rpm to 15,000 rpm for, for example, four minutes or greater.

[0105] In another form, the process may comprise forming a concentrated xanthan gum pre-dispersion comprising all of xanthan gum with part of surfactant, polyol and water; homogenizing the pre-dispersion (using rotor-stator mixer or homogenizer based on pressure) to obtain xanthan particles of 50 microns or less, preferably 0.5 to 40 microns; and then mixing with other remaining ingredients. The process comprises: [0106] 1) premixing 4 to 8 wt % of xanthan gum with 10 to 20 wt % of polyol; [0107] 2) adding and mixing the xanthan and polyol mixture to 75 to 90 wt % surfactant solution with total surfactant level higher than 15 wt %, preferably higher than 20%; [0108] 3) homogenizing the predispersion of (1) plus (2) under conditions sufficient to obtain xanthan particles of 50 microns or less, preferably 0.5 to 40 microns; and [0109] 4) adding and mixing the xanthan gum predispersion of (3) to a mixer containing the rest of the ingredients, mixing preferably being or over 5 minutes.

[0110] Homogenization is a process using a device (e.g., rotor-stator or classic homogenizer as noted above) to break down the xanthan gum particles, typically having particle size between 100 to 400 micrometers, in the said high-polyol containing personal liquid cleanser to form fine xanthan gum dispersion with size 50 microns or less than, more preferably 0.5 to 40 microns. Many different lab and industry homogenizers using various physical technologies to micronize particles in a liquid can be used for this invention. For example, Silverson Mixer Homogenizers are well known rotor-stator mechanical homogenizers known in the industry, and Sonolator is an in-line, high-pressure homogenizer also known in the industry.

[0111] Pro300D homogenizer, which was used to make examples of this invention is a rotor-stator mechanical homogenizer from PRO Scientific.

EXAMPLES

Examples 1 and 2 and Comparative A to F

[0112]

TABLE-US-00001 TABLE 1 Effect of polyol level and processing on liquid cleanser viscosity Examples Prepared by homogenization Comparative examples process Prepared by overhead mixing process (except A) Example 1 Example 2 Comp. A Comp. B Comp. C Comp. D Comp. E Comp. F Na cocoamidopropyl betaine 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Na lauroyl glutamate 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 Xanthan gum 0.6 0.6 0.6 0.6 0.6 0.6 Keltrol CG-SFT Carbopol Aqua SF1 0.9 Hydroxyethyl cellulose 0.9 Methocel 40-100 Glycerin 70 50 6 70 50 6 70 70 Guar Hydroxypropyltrimonium 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 Chloride Jaguar C17 Perfume 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 Phenoxyethanol 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 pH 6.04 6.08 6.20 6.10 6.05 5.95 6.50 6.10 Viscosity, cps (centipoises) Brookfield Rheometer 5020 7040 2340 330 1540 1940 125 Polymer # 5 spindle precipitated 20 rpm, 30 sec; cps at bottom

[0113] The effect of xanthan gum process on liquid cleanser viscosity containing various levels of glycerin is shown in Table 1 above. All samples were prepared using the process described below except at end of processing. First, 6 parts of glycerin (polyol) was weighed and saved in a beaker. All the surfactants, water, and the rest of the glycerin were added to the main mixer and mixed to uniformity for about 10 minutes using an overhead mixer equipped with a 3-blade propeller at room temperature. Xanthan gum and Jaguar C17 powders were added and dispersed to the 6 parts of glycerin saved in the beaker. The xanthan gum dispersion was then added to the main mixer and mixed for 5 minutes at room temperature. Perfume and phenoxyethanol were added and mixed for another 5 minutes. The pH of the cleanser was adjusted to a range of 5.9 to 6.3 using 50 wt. % citric acid or 25 wt % NaOH solution.

[0114] After all the ingredients were added and the pH of the liquid was adjusted, Examples 1 to 2 and Comparative A were homogenized using a Pro300D from Pro Scientific Inc. at 5500 rpm for 5 to 7 minutes. Comparative examples B and C (with composition similar to those of Examples 1 to 2 and Comparative A) were mixed using an overhead mixer equipped with a 3-blade propeller mixed at 700-750 rpm for 10 minutes. Comparative A was mixed in homogenizer, but is considered a comparative because it uses much lower level of polyol. Viscosity of the prepared liquid was measured about 2 hours after the preparation using a Brookfield Rheometer with number 5 spindle at 20 rpm for 30 seconds. The results are given in Table 1. The results clearly shows that xanthan gum processing has a large effect on the liquid viscosity for high polyol (e.g., glycerin) containing liquids. For liquids with a high level of glycerin, Example 1 and 2, the homogenization process gives significantly higher viscosity compared to similar liquid mixed using overhead mixer (Comparative B and C). For liquids with low level of glycerin (Comparative A and Comparative D), the mixing method does not show much difference in final viscosity. It's surprising to find that Examples 1 and 2, with high glycerin, have significantly higher viscosity compared to Comparative A, with low level of glycerin, when both are using the homogenization process. Using the process of this invention, compatability problem of xanthan gum with high glycerol containing liquid cleanser can be resolved; and the efficiency of the gum to thicken the liquid cleanser is also dramatically enhanced.

[0115] Two other examples, Comparative example E and F, were also prepared using other conventional polymeric thickeners, Carbopol Aqua SF1 and Methocel 40-100, for comparison. Both samples were prepared using overhead mixer equipped with a 3-blade propeller and the same procedure described above without homogenization. The viscosity of Aqua SF1 sample as shown in the table is very low, 125 cps, compared to Example 1 of this invention even though higher level of polymer is used than of xanthan gum (0.9% versus 0.6%). The sample containing Methocel 40-100 showed phase separation 2 hours after the preparation. Methocel 40-100 precipitated out of the liquid and formed sticky, gluey lumps at the bottom of the liquid during storage.

Examples 3A to 3F: Effect of Homogenization Speed and Time

[0116]

TABLE-US-00002 TABLE 2 Effect of homogenization speed and time on liquid cleanser viscosity Example 3A Example 3B Example 3C Example 3D Example 3E Homogenization speed and time of xanthan gum in surfactant pre-dispersion Mixing speed 5600 rpm 5600 rpm 5600 rpm 4500 rpm 3000 rpm Mixing time 1 min 3 min 6 min 3 min 3 min Final liquid viscosity Brookfield Rheometer; #5 spindle, 20 rpm, 30 sec Viscosity (cps) Viscosity 3380 4470 3520 3580 Same day after is too low preparation to measure. Viscosity (cps) Xanthan gum gel 4440 4780 4150 4280 Aged 5 day precipitate to at RT bottom of the product.

[0117] Five (5) samples with compositions same as Example 1 were prepared using xanthan gum in surfactant pre-dispersion instead of adding all the ingredient to the mixer and homogenizing the whole batch as described in Example 1. This is the second defined process of the invention. Detail of the procedure is described below.

[0118] First, a glutamate/betaine surfactant premix containing 17.8 wt. % Na lauroyl glutamate and 5.93 Na cocoylpropylbetaine with a pH about 5.9 was prepared. Six (6) parts of xanthan gum powder was mixed with 18 parts of glycerin. The mixture was then added to 76 parts of glutamate/betaine surfactant premix, and homogenized at various speed and time as given in Table 2 (e.g., 3000 to 5600 rpm) using Pro300D homogenizer to make the xanthan gum in surfactant pre-dispersion.

[0119] The final composition was then prepared by adding 68.2 parts of glycerin, 0.05 parts of Jaguar C17, 2.48 parts of deionized water, 17.68 parts of glutamate/betaine surfactant premix described above, 1 parts of perfume and 0.6 parts of phenoxyethanol to a mixer equipped with an overhead mixer. The mixture was mixed using 3-blade propeller at 600 rpm for 10 minutes, following the addition of 10 parts of xanthan gum in surfactant predispersion prepared above. The mixing was continued for another 10 minutes at 600-700 rpm. Viscosity of the liquid was measured about 2 hour after the preparation, and also re-measured 5 days after the preparation. Both data are shown in Table 2. The viscosity data shows that the homogenization process is very robust in controlling the final viscosity of the liquid cleanser. With sufficient mixing, all the liquids have similar viscosity after 5 days storage at room temperature.

Examples 4 to 6

[0120]

TABLE-US-00003 TABLE 3 Example 4 Example 5 Example 6 Na cocoamidopropyl betaine 2.25 1.5 1.5 Na lauroyl glutamate 6.75 4.5 4.5 Glycerin 60 50 50 Guar Hydroxypropyltrimonium 0.1 0.1 0.1 Chloride Jaguar C17 Xanthan gum 1.0 0.8 0.8 Keltro CG-SFT Petrolatum 5 Sunflower seed oil 5 Perfume 1.0 1.0 1.0 Glydant plus 0.3 0.3 0.3 Deionized water To 100 To 100 To 100
pH of the liquid: 5.9 to 6.2

[0121] Examples 4, 5 and 6 of this invention with composition as shown in Table 3 were prepared using the xanthan gum in surfactant pre-dispersion process described in Example 3 above. Example 4 contains high level of total surfactant compared to Example 1, 9% vs. 6%. Examples 5 and 6 contain emollient oil, petrolatum and sunflower seed oil respectively. Both oils were added after the addition of xanthan gum in surfactant pre-dispersion and mixed at 700-750 rpm for 10 minutes. Example 5 containing petrolatum was process at 50 C, and Example 6 containing sunflower seed oil was mixed at room temperature. All the samples are viscous and well structured. Both petrolatum and sunflower seed oil are stably suspended in the liquid cleanser without phase separation at both high and low temperature storage condition.