AU739677B2 - Bars comprising benefit agent and cationic polymer - Google Patents

Abstract

A bar composition comprising a synthetic non-soap surfactant, a hydrophilic structurant, a water insoluble structurant, an oil/emollient benefit agent and a cationic polymer. The cationic polymer has a charge of density greater than 0.007 and is used in a specific ratio to the surfactant.

Description

WO 00/12670 PCT/EP99/05826 1 BARS COMPRISING BENEFIT AGENT AND CATIONIC POLYMER The present invention relates to bar compositions capable of delivering benefit agents to the skin. More particularly the invention relates to bars containing relatively large amounts of hydrophilic structurant the ratio of hydrophilic to hydrophobic being at least 1:2, preferably greater than 40:60, more preferably at least 1:1 and most preferably above 1:1) and in which cationic polymer, particularly cationic polymer having minimum level of charge density, has been found to unexpectedly enhance deposition of benefit agent in such bars.

Cationic polymers are well known in the art. For example in liquid cleansers, cationic hydrophilic polymers such as Polymer JR

R

from Americhol or Jaguar

R

from Rhone Poulenc have been used to enhance delivery of benefit agents (as described in for example EP 93,602; WO 94/03152; and WO 94/03151) Cationic polymers have also been used in bar formulations.

U.S. Patent No. 3,761,418 to Parran, Jr., for example, teaches detergent composition (including bar soaps) containing water insoluble particulate substances such as antimicrobial agents and certain cationic polymers to enhance deposition and retention of such particulate substances. Although bar soap formulations are used in the examples, all of the formulations are primarily structured with soap and/or fatty acid. Further, not only are benefit agents (oils/emollients) not disclosed, but it would also be WO 00/12670 PCT/EP99/05826 2 expected that hydrophobic structurants would interfere with deposition of any such oils/emollients.

WO No. 95/26710 to Kacher et al. (assigned to P&G) teaches skin moisturizing and cleansing bar containing skin cleansing agent and lipid moisturizing agent. A preferred optional ingredient is one or more cationic polymeric skin conditioning agent added to provide a tactile cue. Again, however, the bar is made of a rigid crystalline network structure consisting essentially of selected fatty acid soap material. The applicants have found such fatty acid soap material to be detrimental to deposition.

U.S. Patent No. 5,425,892 to Taneri et al. teaches personal cleansing freezer bars comprising a skeleton structure of neutralized carboxylic acid soap. The patent teaches polymeric skin feel aids, water soluble organics and oils.

However the bars, as noted, have a distinctive carboxylic acid structure differing from bars of the invention containing relatively large amounts of hydrophilic structurant.

Hydrophilic structured bars themselves are also taught, for example, in U.S. Patent No. 5,520,840 to Massaro et al. or U.S. Patent No. 5,540,854 to Fair et al. There is no teaching in these references, however, of cationic polymers, and no suggestion that such cationics could enhance deposition of oil/emollients in bars containing relatively large amounts of hydrophilic structurant. Further there is no teaching or suggestion in this or any other reference of a critical cationic to surfactant ratio above which 15-1 1-2000' EP 009905826 J6473/1 -3dep~i~iO o O~S/IUO.3ietr is significanly enacd9 that CatiOrnics Must hav i~mZl eeko"l~~ed8.Y Firna1o.y. U' Patent No. S,262,079 to KOC'her 'at teaches mild neutral pl, cleazi.Si bar comprising S -50% by 'wtumonocarboy~ylic fatty acidrs (wb.±ch provides Skeletal stru~tUre), 20 to 65% bax firma.eso aid *nd I.S* to 55" watex.

Th. bars may contain opt±Voal PoJ1Y01rS (0).40r) so *bax fi~mnesr aids". the bars are PT.ima~iy fatty acid strucOtured, and tbs OnlY bar firmne%8sS aide. "CO~lified axe isetiornate they do not have minimum levels of bydZophi).ic to hyfdr0Ph~biC sr'ctUrat) Further, catioti~cs disclosed are S~lr, quater~i5d quar e-tc., al~l of which have c-harge density below 0.007- There is thus no recognitionl is that onily catioflic polymers kjavrig a minim=~U1 charge activitY are adequate for 'purpose of thie inrvention.

suidden1y and unexpectedly, the applican'ts have d4iscovered that catiofic, cationlic polymes~ of a mnmmcag density level, cam be used to erahxlce depositionL of ojls/emllients in bars compr±iig a relatively large am0W7t of hydrophilic sutrtJn1 Che ratio of pka-pai to hydrophobiC structur~t being at least 112 preferably great.er than 40:60, more preferably at least and mosit 2S preferably above 1:1 f SZ ar hydrophobic structuran.e*6eads 't8 ydO

;L.

structurant by no mor'e than '10% by wtj'ht bf .tbe total Composition) and~ ±uiater that Lbhere is a minimulT' britic8.l rati.o of Cationhic polymer to surfactanc at wk iih depositionl is remarkably enhmflC~d. In% additionL, icrtaltt levels of sxrfactaft, particularly aniollic, -not excceed AMENDED SHEET WO 00/12670 PCT/EP99/05826 -4 certain ranges (lest deposition be affected), and that minimum amounts of oil/emollient be used.

More specifically, the subject invention relates to bar compositions comprising: 10 to 50%, preferably 20% to 40% by wt. of a synthetic, non-soap surfactant, preferably an anionic surfactant acyl isethionate or alkali metal lauryl ether sulfate); 10 to 40%, preferably 15 to 35% by wt. of a hydrophilic structurant having a melting point in the range 400 to 100 0 C (such structurant will generally have solubility of at least 10% at room temperature); 5 to 20% of a water insoluble structurant with MP in range 40 0 C to 200 0

C;

2% to 40%, preferably 5% to 20% benefit agent; and 1.0% to 10% cationic polymer; wherein the amount of insoluble structurant and soap, if any, present exceeds the amount of hydrophilic structurant by no more than 10% by wt. total bar composition; wherein the amount of cationic polymer is such that ratio of cationic to surfactant is 0.06 to 1 to 1:1, more preferably 0.08:1 to 0.5:1; and wherein the charge density of cationic polymer (number of monovalent charges per repeat unit divided by molar mass of repeat unit) is greater than 0.007.

',-11i-2000 EP 009905826 J6473/1 The inivenltionl will n~ow be further described by way o~f e~aPle only with reterence to beaOm nYdavfgir Wbich.

Fisu~e I showa depouitiem results depending Ont ratio of cationi~c to siifactaft- Agi seen, onlY Wheni ratio Of car oi o atn reaches certain miim~um Leve:l does deposition Signiificantly increase.

3.o Tkhe peSflt inventioni relates to relatively lOW activJe bars sot active, preferably less than 404, more Prcef~aly 3oqr arid less active) wherein there Is present a relatiVely lare anoiltOf hydrophilic structrant (jX'k*V st~atuXrflt and soaLp, if PreB"Lt comprisBes no .aOre tha~n about 1.ot by wt =;ore tban am=~t Of hydx0Pbhi stru.cturaSXt and which further comprise'3 10 1&tively laige amount. of oil/emollient at least Unexcpectedly, the applicants~ have discovered that wliefl the ratio 02 Cationie, to surf actart in such bare is equal& 3 to or abovea certain defiued ratio, tha deposition of benefit agent fromi the bar- is remarkably enhanced. The catioaic polymers used r~.st also have Mi r. defined leVels of chaxgSdniY The bar is described in greater detail below.

The bars of the lnyvritian. c~atLt n from about -io0i to Svt by wt.. mor -preferbly 15 to 40%- of a e"nt~ tic. =Ofl soap surf actant suitable surf actarits are generally selected from the group consisting of anionice rionioniC, ax!photeric, 2w~terionjc and/or catioic sujrfactafts and mix~tures thereof such as are well kcnovm ji the art.

AMENDED SHEET WO 00/12670 PCT/EP99/05826 6 More specifically, the surfactant system will generally comprise at least one anionic surfactant, a zwitterionic surfactant or, preferably mixtures of anionic or anionics and zwitterionic surfactant.

The anionic surfactant which may be used may be aliphatic sulfonates, such as a primary alkane Cg-C 22 sulfonate, primary alkane

C

8

-C

22 disulfonate,

C

8

-C

22 alkene sulfonate, C 8

-C

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 C 12

-C

18 alkyl sulfate) or alkyl ether sulfate (including alkyl glyceryl ether sulfates). Among the alkyl ether sulfates are those having the formula:

RO(CH

2 CH20)nSO3M wherein R is an alkyl or alkenyl having 8 to 18 carbons, preferably 12 to 18 carbons, n has an average value of greater than 1.0, preferably greater than 3; and M is a solubilizing cation such as sodium, potassium, ammonium or substituted ammonium. Ammonium and sodium laurel ether sulfates are preferred.

The anionic may also be alkyl sulfosuccinates (including mono and dialkyl, C 6

-C

22 sulfosuccinates); alkyl and WO 00/12670 PCT/EP99/05826 7 acyl taurates, alkyl and acyl sarcosinates, sulfoacetates,

C

8

-C

2 2 alkyl phosphates and phosphates, alkyl phosphate esters and alkoxyl alkyl phosphate esters, acyl lactates, Cg-C 2 2 monoalkyl succinates and maleates, sulphoacetates, alkyl glucosides and acyl isethionates.

Sulfosuccinates may be monoalkyl sulfosuccinates having the formula: R o 2

CCH

2

CH(SO

3

M)CO

2 M; and amide-MEA sulfosuccinates of the formula

R

1

CONHCH

2

CH

2 0 2

CCH

2

CH(SO

3

M)CO

2

M

wherein R ranges from C 8

-C

22 alkyl and M is a solubilizing cation.

Sarcosinates are generally indicated by the formula

RCON(CH

3

)CH

2

CO

2 M, wherein R ranges from C 8

-C

2 0 alkyl and M is a solubilizing cation.

Taurates are generally identified by formula R2CONR CH 2 CH 2

SO

3

M

wherein R 2 ranges from C 8

-C

20 alkyl, R 3 ranges from C 1

-C

4 alkyl and M is a solubilizing cation.

U 1:1 4 01516411817..-- +98 25-08-2000 EP 009905826 Particularly prefer-red are the Ce-Cis acYl isethionates.

These esters are prepared by reaction between alkali metal i~ethionate with mixed aliphatic fatty acids having fromn 6 to 18 carbon atoms and an iodine value of -less than 20, At least 75% of L1ae mixed fatty acids have from 12 to 18 carbon atoms and up to 25% have from 6 to 10 carbon atoms.

Acyl isethionates, when present, will range from about to about 50% by weight of the total bar composition.

Preferably, this component is present from about 201% to about The acyl isethionate may be an alkoxylated isethionate such as is described in Ilardi et U.S. Patent No. 5,193,466, hereby incorporated by reference.

Anionic surfactant may also be a 'soap". By soap is meant alkali metal salts of aliphatic alkane- or alkene monlocarboxylic acids, more generally known as C 1 2

-C-

2 2 alkyl.

fatty acids. Sodium and potassium salts are preferable. A preferred soap is a mixture of about 15% to about coconut oil and about 55t to about 85% tallow.

The soaps may contain unsaturation in accordance with commiercially acceptable standards. Excesuive ursaturation is normally avoided.

The anionic component will comprise from about 10% to 50% of the bar composition.

AMENDED SHEET.

25-08-2000 (C) 4u- a- V -11: 14- O15S16411817, +149 89 2'qW&9-- e-- EP 009905826 9- Amphoteric d etergents whicli may be used in this invention include at least one acid group. This may be a carboxylic or a sulpkionic acid group. They include quaternary nitrogen and therefore are quaternary amido acids. They should generally include an alkyl or alkenyl group of 7 to IS carbon atom~s. They will usually comrply with an overall structural formula; R LC-NN (CK2)Ujm-N -CY where R Iis alkyl or alkenyl of 7 to IS carbon atoms; R 2 and R 3are each independently alkyl, hydroxyalkyl or carboxyalkyl of 1 to 3 carbon atoms; n is 2 to 4; M is 0 to x is alkylene of 1 to 3 carbon atoms optionally aubstituted with hydroxyl, and y ise -CO 2 Or -SO3 Suitable amphoteric detergents within the above general formula include simple betaines of formula: R1 12C2 and amido betaines of formula: AMENDED SHEET 015164-1 1817 2520~8-2000 (c) +4-9 89 23904N4: a -7 EP 009905826 10 R C0NIJ(Cj2) u.Nt- CH 2 CO2' where m. is 2 or 3.

in both formulae R1is alkyl or alkenyl of 7 to IS carbons; and R2and R3are independently alkyl, hydroxyal(yl* or carboxylalkyl of I to 3 carbons.lz may in particular be a MiXtUre Of C1.

2 and C1.

4 alkyl. groups derived from coconut so that at least half, preferably at least three quarters of the groups R have 10 to 14 carbon atoms. R 2and R3 are preferably mnethyl.

A further possibility is that the amphoteric detergent is a suiphobetaine of formula: I4 -(CH2) 3 S0 3 ,AMENDED SHEET- WO 00/12670 PCT/EP99/05826 11

R

2

R

1

-CONH(CH

2 )m (CH 2 3 S0 3

R

3 where m is 2 or 3, or variants of these in which -(CH 2 3 S0 3 is replaced by

OH

I

-CH

2

CHCH

2

SO

3 In these formulae R R and R are as discussed for the amido betaine.

Amphoteric generally comprises 1% to 10% of the bar composition.

Other surfactants nonionics, cationics) may also be optionally used although these generally would not comprise more than .01 to 20% by wt. of the bar composition.

Nonionic surfactants include in particular the reaction products of compounds having a hydrophobic group and a reactive hydrogen atom, for example, aliphatic alcohols, acids, amides or alkyl phenols with alkylene oxides, especially ethylene oxide either alone or with propylene oxide. Specific nonionic detergent compounds are alkyl (C 6

C

22 phenols-ethylene oxide condensates, the condensation 15-1 1-2000 EP 009905826 *J6473

(C)

produ~cts Of aliphatic (CO-CIB) priMary or Seconldary liZer ox bran~ched alcohol.s with ethylelG oxide, an~d productB mde by cone~S~iO1 o ety~.Z18oxda with tUim reactiOn PTOductU o propylefle oxide and OthYle1daL~l tn ocle non:Lo.nic deteg~ compouncds include lone chain terti.X? ami~ne oxids# 1=g chain ,zertiX~y yhosehinQ oxides and diai.kyl su1phO~ideS.

rho ne:LiOic may also be a sugar amidOO such as a, polysaccharide amide. Specifically, the slfffactant may be one of the la tob1.omAtid deScribedin1.. aelW.

5,389,219 to Au et al. wihi we~ nopztdb referenlce and VoI'y(hydrxyy&m~des suei as described in U.S.

patent NO. 5,312#954 to 110tton at. %Qraby jarorpoatd ,is into the uubet.&ppliai by ref ereic.

ExamIples of cationic detergenlts are the quate?~m-Y abOni.WI compounds such as al1dinwthYlaumrium~ halOgenider o ~o ther~ s=factants which may be used are described in U.S.

Patent N7o. 3/?23323 to Parran Jr. ad "Surface Ac tiv* Agents and Detergents" (Volume I 1; by Schwa&_tv, PerKY 3ezc'h, both of wlich are also iacorporated &.nto the subject application by referencepreferred compositionl comprises at least 104* acy 2 isethioflate and It% to 10% betaifle.

-Xnohercritic&a. cuipowid Of th Ar i ~r6Pic struct.an1t polyalkylone glycol)- AMENDED SHEET 1-1 1-2000 EP 009905826 a6413 (C) 13 This comPOneflt comnPriseo 10% by Wt. to 40%, preferably.

to 31% -bY ba co~oii The rstrurt~ant has a malting~ poin~t of 400't.0 100 0

C,

s preferabl.y 45*C to 1000C, More Fztisrably 505 o9C Cmenerally these itructuran3ts will be at lea~t 10k water solu~ble at room temperature.

Materials WhiCe1 are en~visaged as the water solu~ble atructuxant Wb are moderately bigt moleculr weight polyalkylena oxides of Appropriate melting point and in particular polyethylene glycols or iures thereof.

poyethy3ln glycols (PEG's) which may be used m~ay hame a molecular weight in the range 1,500-20,00,.

It should be understood that each product Union Carbide I s Carbowaxe (PO8OO ersents a distributiO2 of Molecular Weishts. Thurs PSG B,.000, for exmple, bas an average toW razgeof 7,000-9,000, whileB PEG 300 has am average MW range.frol 28S to 315. Th~e average M4W of the product can be anywhere between~ the low azd hil"O" valuei anLd there may still be a good portion of the material with

MW

below the low value and above the high valuje.

in some em~bodimfents of this in.venltion ;Lt is preferred to include a fairly-smnall quaftit;.y of polyalkylene glycol polyethyliml* glycol) witrh a molecular weight in the range trom 50,000 to 500,000, espeCially molecul2ar weights of around !00,0010. Such polyethylene glycols have been AMENDED SHEET WO 00/12670 PCT/EP99/05826 14 found to improve the wear rate of the bars. It is believed that this is because their long polymer chains remain entangled even when the bar composition is wetted during use.

If such high molecular weight polyethylene glycols (or any other water soluble high molecular weight polyalkylene oxides) are used, the quantity is preferably from 1% to more preferably from 1% or 1.5% to 4% or 4.5% by weight of the composition. These materials will generally be used jointly with a larger quantity of other water soluble structurant such as the above mentioned polyethylene glycol of molecular weight 1,500 to 10,000.

Some polyethylene oxide polypropylene oxide block copolymers melt at temperatures in the required range of 40 to 100 0 C and may be used as part or all of the water soluble structurant Preferred here are block copolymers in which polyethylene oxide provides at least 40% by weight of the block copolymer. Such block copolymers may be used, in mixtures with polyethylene glycol or other polyethylene glycol water soluble structurant.

In addition, there may be a mixture of lower and higher MW polyalkylene glycols as described in U.S. Patent No.

5,683,973 to Post et al., hereby incorporated by reference into the subject application.

It should be noted that, although they may not necessarily be used by themselves, certain water soluble adjuvant fillers may be used in combination with the water soluble 01S16411817-. +4r9 893 23994465:#1c) 2S-08-2000 EP 009905826 sructurant. Among these, for example, are included maltodextrin =nd similar water soluble starches. It inc3.udedj, these adjuvants would comprise no more than about by wt. of the composition.

The water insoluble structurants are also required to have a melting point in the range 40-200 0 more preferably at least 0 OC, notably 50 0 C to 90 0 C. suitable materials which are particularly envisaged are fatty acids, particularly those having a carbon chain of 12 to 24 carbon atoms. Examples are lauric, myristic, palamitic, stearic, arachidonic and behenic acids and mixtures thereof. Sources of these fatty acids are coconut, topped coconut, palm, palm kernel, babassu and tallow fatty acids and partially or fully hardened fatty acids or distilled fatty acids. Other suitable water insoluble structurants include alkanols of 8 to 20 carbon atoms, particularl.y cetyl alcohol. These materials generally have a water solubility of less than Sg/litre at The relative proportions of the water soluble structurants and water insolubole atructurants govern the rte at which the bar wears during use. The presence of the water insoluble structurant tends to delay dissolution of the bar when exposed to water during use and hence retard the rate of wear.

In general, insoluble structurant will comprise 5 to 20% by wt. of the composition.

-AMENDED SHE- 11 -2b00 EP 009905826 J647fll Accordin- ___-_inUtf .rtr noul "doesrnot eceed the amount 6f 'yzp±C trizt-arant plus aUY~ moap whiCh iray be XLfntWMr .ha. abo. r. I~ while not wi shing to be bound by theory, this is believed to be so becauss Whefl there Is too muich soap and/or hydzoPhillc Brrt~u"At level of depositicn is reduced.

The benef it age~t Of the COMiOSition15 of tb* invention is included in the coi~iositions to moistuzeZS Condition and/or protect the akizi. By "benefit agent" is raeant a substance that sefte?&6 the. sk~in (stratm conuIT) and keeps it soft by retarding the de.crease of its warexr content and/or protects the skin.

Preferred benefit agents include: silicone 011s, gums and modifications thersofsuch as linear and cyclic polydimethylsiloxalnCsI amino, alkyl alkyaryland aryl silicone oils; fate and oils including~ natural fate and oils such as lojoba, soybeans sunflower, rice bran, avocado, alw'ond, olive, Became, persic, castoro co 0 onutj mi~nk oils; cacao fat, beef tallow, lard; hardened oils. obtained by hiydogenatinlg the aforemenitionled oils; and synthetic mono, di anid triglyceZrids ouch as myristic acid glyceride and 2ethyiheaoi acid glyceride 1 waxes su~ch as carriaubu.. sperrnoceti, beeswa2%. lanolin and derivatives .thereof; hydrophobic plant cetractaF AMENDED

SHEET

WO 00/12670 PCT/EP99/05826 17 hydrocarbons such as liquid paraffins, petroleum jelly, microcrystalline wax, ceresin, squalene, squalane, and mineral oil; higher fatty acids such as lauric, myristic, palmitic, stearic, behenic, oleic, linoleic linolenic, lanolic, isostearic and poly unsaturated fatty acids (PUFA) acids; higher alcohols such as lauryl, cetyl, steryl, oleyl, behenyl, cholesterol and 2-hexadecanol alcohol; esters such as cetyl octanoate, myristyl lactate, cetyl lactate, isopropyl myristate, myristyl myristate, isopropyl palmitate, isopropyl adipate, butyl stearate, decyl oleate, cholesterol isostearate, glycerol monostearate, glycerol distearate, glycerol tristearate, alkyl lactate (for example lauryl lactate), alkyl citrate and alkyl tartrate; essential oils such as fish oils, mentha, jasmine, camphor, white cedar, bitter orange peel, ryu, turpentine, cinnamon, bergamont, citrus unshiu, calamus, pine, lavender, bay, clove, hiba, eucalyptus, lemon, starflower, thyme, peppermint, rose, sage, menthol, cineole, eugenol, citral, citronelle, borneol, linalool, geraniol, evening primrose, camphor, thymol, spirantol, pinene, limonene and terpenoid oils; lipids such as cholesterol, ceramides, sucrose esters and pseudo-ceramides as described in European Patent application No. 556,957; vitamins such as vitamin A and E, and vitamin alkyl esters, including those vitamin C alkyl esters; sunscreens such as octyl methoxyl cinnamate (Parsol MCX) and butyl methoxy benzoylmethane (Parsol 1789); phospholipids; WO 00/12670 PCT/EP99/05826 18 humectants such as glycerin, propylene glycol and sorbitol; and mixtures of any of the foregoing components.

Where adverse interactions between the benefit agent and surface active are likely to be particularly acute, the benefit agent may be incorporated in the compositions of the invention in a carrier.

Such benefit agents include lipids; alkyl lactates; sunscreens; esters such as isopropyl palmitate and isopropyl myristate; and vitamins. The carrier can, for example, be a silicone or hydrocarbon oil which is not solubilized/micellized by the surface active phase and in which the benefit agent is relatively soluble.

Particularly preferred benefit agents include silicone oils, gums and modification thereof, esters such as isopropyl palmitate and myristate and alkyl lactates, and vegetable oils such as sunflower seed oil.

The benefit agent can be provided in the form of an emulsion.

The benefit agent of the invention may also function as a carrier to deliver efficacy agents to skin treated with the compositions of the invention. This route is particularly useful for delivering efficacy agents which are difficult to deposit onto the skin or those which suffer detrimental interactions with other components in the composition. In such cases the carrier is as often a silicone or hydrocarbon WO 00/12670 PCT/EP99/05826 19 oil which is not solubilized/micellized by the surface active phase and in which the efficacy agent is relatively soluble. Examples of such efficacy agents include antiviral agents; hydroxycaprylic acids; pyrrolidone; carboxylic acids; 3,4,4'-trichlorocarbanilide; benzoyl peroxide; perfumes; essential oils; germicides and insect repellents such as 2,4,4'-trichloro-2'-hydroxydiphenyl ether (Irgasan DP300); salicylic acid; willow extract, N,N-dimethyl mtoluamide (DEET); and mixtures thereof.

The benefit agent comprises 2 to 40%, preferably 5 to 20% by wt. of the composition.

Finally, the cationic polymer (deposition aid) is a water soluble cationic polymer or copolymers having a molecular weight from about 1,000 to 2,000,000 and a high cationic charge density. Specifically, the cationic charge density should be at least 0.007 and higher where cationic charge density is defined as number of monovalent charges per repeat unit divided by the molar mass of repeat unit.

(R)

Thus, for example, a Jaguar type cationic such as Jaguar

(R)

C14S (such as used in example RR of Kacher et al. Patent No. 5,262,079) has charge density of 0.0008, below the threshold of invention as does [N-[-3-(dimethylammonio) propyl] urea dichloride (Mirapol A15 which has charge density of 0.00661. By contrast, dimethyldiallylammonium

(R)

chloride (Mirquat 100 has density of 0.00793 and is within the invention.

0 U 1:IS O56i87 +49 8q 1>'QAZ'.

25-08-2000 EP 009905826 It is also important for the cationiC polymer to be (a) fully hydrated prior to incorporation in the bar formulation and at a concentration Of 1% by wt. or higher for the desired benefit, enhianced deposition, The commercial application (usefulness) of the said invention would therefore require the cationic. pol.ymer to be at a relatively high concentration When hydrated to avoid the impracticality, difficulty and high costs of drying the syndet bar formulation. A cationic polymer such as dimethyldiallylammnfium chloride (Tradename Mirquat 1-00) can be prepared at concentrations of 40W (60% water), whereas the low charge density quaternized guar cationic polymer (Tradeniame Jaguar C14s) exemplified by 1Xacher et al. can only be prepared at concentrations of approximately 3t (97% water) and are not practical on a commercial scale.

Exemplary cationic polymers which may be used according to the invenition include salcare(V type polymers from Allied Colloids, and Merquate type polymers from Calgon.

Those cationic polymers which are Senerally not applicable according to the invention are the high molecular weight, low charge density polymers such as Polymer JR.-4000 from .Amerchol and cat ionic polysaccharides of the cationic guar 2S gum class such as Jaguar C140) from Rhone-Poulenc.

It is an important aspect of the invention that there be a minimum amount of cationic polymer be used. The ratio ot cationic to su±rfactant is 0.06:1 to 1:1, more preferably 0. 08 to 1 to 0. 5 to 1.

AMENDED SHEET WO 00/12670 PCT/EP99/05826 21 In addition ratio of hydrophilic structurant to total of soap and hydrophobic structurant should be at least 1:2, preferably 40:60, more preferably at least 1:1 and most preferably greater than 1:1.

Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts or ratios of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word "about".

Further, when used in the specification and claims, the term comprises or comprising is to be understood to specify the presence of stated features integers, steps, components etc., but not to preclude the presence or addition of one or more features, integers, steps, components or groups thereof.

The following examples are intended to further illustrate the invention and are not intended to limit the claims in any way.

EXAMPLES

MATERIALS AND METHODS Materials Sodium cocoyl isethionate was supplied by Lever Baltimore, Polyethylene glycol (PEG 8000) was supplied by Union WO 00/12670 PCT/EP99/05826 22 Carbide, and Merquat 100 (cationic polymer) was supplied by Calgon Corporation. Polydimethylsiloxane (PDMS) with viscosity of 60,000 cs was from Dow Corning, Maltodextrin was from Grain Processing Corp., and the cocoamidopropyl betaine was from Goldschmidt Palmitic, stearic acid, and sodium stearate were supplied by Unichema.

In-Vivo Deposition Measurements Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) was the analytical technique used to measure silicone deposition. The standard procedure is documented below.

Formulation Processing Bar formulations were prepared in a 2-liter Patterson mixer.

The fatty acid and sodium stearate were mixed together at 0 C. Cocoyl isethionate was then added followed by the betaine and minor ingredients. After mixing for thirty minutes and drying to approximately 7% water, a polyethylene glycol and maltodextrin was added. This was mixed for an additional ten minutes. The cover was removed and the silicone and Mirquat 100 were added. The moisture content was determined by Karl Fisher titration with a turbo titrator.

At the final moisture level the formulation was dropped onto a heated applicator roll and then was chipped over a chill roll. The chill roll chips were plodded in a Weber Seelander duplex refiner with screw speed at -20 rpm.

WO 00/12670 PCT/EP99/05826 23 The nose cone of the plodder was heated to 45-50 0 C. The cut billets were stamped using a Weber Seelander L4 hydraulic press with a nylon, pillow-shaped die in place.

The incorporation of benefit agent

(R)

polydimethylsiloxane) into Dove -like compositions high acyl isethionate bars structured with fatty acid) or primarily soap based compositions results in negligible deposition of the benefit agent. High surfactant levels 60%) and insoluble structurants fatty acid), generally inhibit transfer of benefit agent onto the skin.

Even addition into lower active, hydrophilic structured bars such as those taught in U.S. Patent No. 5,520,840 to Massaro et al. result in little deposition. In order to study effect of cationic polymer in such low active, hydrophilic structurant bars, however, the following compositions were prepared.

WO 00/12670 PCT/EP99/05826 24 TABLE 1 Component Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. Na cocoyl isethionate 18.75 22.5 26.25 30.0 30.0 PEG 8000 25.75 21.0 16.25 15.5 11.5 Merquat 100 1.0 2.0 3.0 0 PDMS (Polydi- 10.0 10.0 10.0 10.0 10.0 methylsiloxane) Palmitic-Stearic Acid 14.0 14.0 14.0 14.0 14.0 Maltodextrin 8.0 8.0 8.0 8.0 Na Stearate 5.0 5.0 5.0 5.0 CAP Betaine 5.0 5.0 5.0 5.0 Na Isethionate 2.2 2.2 2.2 2.2 2.2 Target Water 4.0 4.0 4.0 4.0 PEG 540 5.0 5.0 5.0 5.0 Coconut Fatty Acid 1.1 1.1 1.1 1.1 1.1 In general, compositions were prepared by mixing ingredients at temperature sufficiently high to provide mix, cooling on chill roll to form chips/flakes, extruding, cutting and stamping. Compositions made are set forth in Table 1 above.

Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTI) was the analytical technique used to measure silicone deposition. In the standard procedure, the test bar is wetted and rotated ten times in the hand, the inner forearm is then wetted and the bar is rubbed ten times on the forearm. This is followed by a thirty second wash and a fifteen second rinse. The arm is then dried and an infrared scan of the inner forearm is obtained. The silicone is quantified by integrating the absorption band between 770cm and 835cm This is plotted on a standard curve and the deposition value in ug/cm 2 is reported.

WO 00/12670 PCT/EP99/05826 25 The deposition results of the experimental design formulations are summarized in Table 2 and depicted graphically in Figure 1. The wide variance observed is due to different skin types and skin conditions, requiring a minimum of approximately 8 independent measurements per prototype.

Table 2: In-Vivo Deposition of Experimental Design Bars Example SCI Merquat Deposition Std.Dev. N Wt. Ratio ug/cm2 of Merquat

/SCI

Ex. 4 30.0 0.0 0.4 0.8 9 Ex. 1 18.75 1.0 1.5 0.9 8 0.053 Ex. 2 22.5 2.0 7.8 8.5 16 0.089 Ex. 3 26.25 3.0 9.4 7.4 17 0.114 Ex. 5 30.0 4.0 11.3 9.3 19 0.133 As can be seen, the amount of oil deposited on the skin appears to be a function of the cationic polymer to surfactant ratio. Specifically, a minimum ratio of 0.06 seems to be required. In the absence of polymer, virtually no silicone is detected on the skin from the bar prototypes.

When the polymer:surfactant ratio is increased, a considerable increase in deposition is observed.

The following formulations were selected for further deposition.

WO 00/12670 PCT/EP99/05826 26 Component: Ex. 6 Ex. 7 Ex. 8 (Body Wash) Na Cocoyl Isethionate 30.0 40.0 PEG 8000 13.0 10.0 0 PEG 540 5.0 5.0 0 Cationic Polymer 2.5 2.5 0.55 Polydimethyl Siloxane 10.0 10.0 Palmitic-Stearic Acid 14.0 14.0 0 Na Laureth Sulfate 0 0 CAP Betaine 5.0 5.0 5.6 Lauro Amphoacetate 0 0 5.6 Isostearic Acid 0 0 Maltodextrin 8.0 5.0 0 Na Stearate 5.0 5.0 0 Na Isethionate 2.2 2.2 0 Water 4.0 4.0 qa. 100 For Example 6, ratio cationic/surfactant 0.083 For Example 7, ratio cationic/surfactant 0.0625 Example 6 contained 30% sodium cocoyl isethionate (SCI) with Merquat and 10% PDMS. In Example, the SCI was increased to 40%. The Merquat and PDMS levels were not changed.

The deposition results from the formulations are depicted in Table 4 below: WO 00/12670 PCT/EP99/05826 27 Table 4 Experiment Deposition 4g/cm2 Ex. 6 14.5 10.3 Ex. 7 17.2 Ex. 8 0.8 1.3 Table 4 also compares in-vivo deposition from the bar prototypes (Examples 6 7) to a liquid body wash (Example As noted, significantly higher levels of oil are deposited on the skin from the bar prototypes.

Claims (11)

1.Wi 00 EP 009905826 -28 I. A bar composition comprising: 10% to 5o% by wt. synth~etic non-soaR surfa.-tant S selected from the group consisting of anionic, inon±Oriic,. cationic, amphotesio/zwitterionic surfactants and mnixtures thereof; 10% to 40% by wt. of a hydroph~ilic sLcuctuSrflt having a melting point in the range 40') to 1006C; c)5% to 20b-by wt. of a water insolubl.e structurrL with MP 40 to 200OC; 2% to 40%1 of a benefit agent that softens the akcin and k~eeps it soft by retarding the decrease of Its wdater contenlt and/or protects the skin; 1.0% to 104 by wt. caLionie polymer having a molecular we±.ght of from 1000 to 2,000p000 wherein the amiounrt of insoluble structurant and soap; if any, exceeds amount of hydrophilic structurant by no more than 10t by wt. of total bar composition; and wherein the amount of cati.onic polymer is such that ratio of caLicrnic polymer to surfactant is 0-06:1 to anid wherein charge density of cationic polymer is greater than .0.007; and wherein the ratio of hydrophilic to hydrophobic structurant is at least 1:2.

2. A composition according to claim It wlherein surfactant~ is an anionic surfactant.

3. A compositionl according to claim 2, wherein surfactanlt is acy. isethionlate or alkali metal alkcyl ether sulfate. AMENDED SHEET -Iv1 !tfooO EP 009905826

4. A composition according to any of the precediLng claims, comprising 15 to 401 by wU.

5. At composition according to any of the pr~eceding claims, comprising 15 to 3S* by wt.

6. A compo~ition according to &Ay of the preceding claims, wherein the hydrophilic structuralt is at least water soLuble at room tempezature-

7. A composition according to any of the preced.ing claims, wherein the hydrophilic structurant is selected f rom polyalkylefle oxides,' having MW 1500 to 20,000 and block 15 copolymexs of polyethylene anid pol.ypropylenel Ocider anld thereof.

S A composition according to any of t~he preceding claitms, wherein the insoluible structurant is C12 to C211 fatty acid.

9. A composition according to any of the preceding Claims, wherein the benefit agent comprises 5 to 20% by wt. of the ccapa8itiofl.

A compositioni according to any of the preceding claims, comprising 1.0% to cationicd polymer.

11. A composition according to any of Lhe preceding claimsa, wherein 'the ratio of cationic to surfactant is in the region 0.08:1 to 0.5 to 1. AMENDED SHEET TOTF~L P.11.I