CA2340706A1 - 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

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 {i.e. 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, l0 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 axe primarily structured with soap and/or fatty acid. Further, not only are benefit agents (oils/emollients) not disclosed, but it would also be 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 ..... . __ - _ .____ . _. _ _ .. _ _ . . ._ __ 15-11-2000 ' '' EP 009905826 ~5~73/1 -r -d~epvsitior~ of oils/ecaolliaat= is eigni..~iaat~tly er~hsneed oz Chat cat Tonics mus t haws m~.ni~m level of Ghax$e density.
Fixsally. U.6. patent No. 5.~6a.n~9 to Kscher et .a:,. ~teache~
firm, caild reutrai p'~ clearuiz~g bar~ comprising ~-50~t by vrt.
moaocarboxYlic fatty acids lwhich providss skeletal structure . ~fl to 65% bar f3.r~ee~ aid and 15% to 55% water.
The b$rs may contain optio~.l pol.yols (0-~0%~ as 'bar f~.r~eae aids:" . °The bars are psitaar~.ly fatuy acid stractu~cad. and th~a only bar fires aide ~#x4c~litiaa ar~
isethionate t i , a . . they do not hx~ c~i~.t~um levels of hyd~tophilic to b,~rdzophobic szructusaatl . Furtlaar. catioriie$
disclosed are guLar. ~ateraiaed etc. , all ef wh.~.Ch have cue deity below 0.00. There i9 thus no recognition that only aatioa3c polymsr$ having a minimum ch~3e activity are ad~quate for.purPose of the ia~"eation. .
Suddenly and unexpecte~dlY. the applicants have . d3.mcovarod that catioaics, i.~o.. cation~,c polYme~'$ of a minimum Charge 24 density level, can be need to enhance deposition of oils/emollients is~ bars comprising a relatively large amount . f h o hilic structurant te.g~ . the ratio of .hY~o~lic o y~ p to hydrophobic structuraat being at least 1:2. preferably greater than ao:60, more preferzbly at least 1:1 and roost a5 preferably above ~. : ~. ; f~her cha th~~Q z~°a~~~ - _u. --~ ..
h drophobic strucGUSar~t.,t'ed~ ''tn'tv '.f'iydrop'hi1ic, ~ " , no ;hare tha,a 10 % by we i~ght o f ~~he . -tof al- . , .._ -. ,.
mtruccuraat bY : , ... ... .
Gocnpositio~s) an3 further that ~~there is a ~.ni~m o=ltica3.
raz ~.o of c:3tioaic y~olY~e= to surf acts.nt at which deposition o .is remarkably enhanced. In addition, it is critical chat ~.evels of sur'~a~tant, pa~rticuiar7.Y aaiot~ic, -_iot exceed AMENDED SHEET

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:
(a) 10 to 50%, preferably 20% to 40% by wt. of a synthetic, non-soap surfactant, preferably an anionic surfactant (e. g., acyl isethionate or alkali metal lauryl ether sulfate);
(b) 10 to 40%, preferably 15 to 35% by wt. of a hydrophilic structurant having a melting point in the range 40° to 100°C (such structurant will generally have solubility of at least 10% at room temperature);
(c) 5 to 20% of a water insoluble structurant with MP in range 40°C to 200°C;
(d) 2% to 40%, preferably 5% to 20% benefit agent; and (e) 1.0% to 10% cationic polymer;
wherein the amount of insoluble structurant (c) and soap, if any, present exceeds the amount of hydrophilic structurant (b) by no more than 10% by wt. total bar composition;
wherein the amount of cationic polymer (e) 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.

15-11-2000 1 , EP 009905826 .
,~64~3I1 The invention will now be gurth~r desGribad by way of example only with r~ference to the accompanying drawing. in which:
~i~e, 1 shows dsposit~.°n =saults depend~.n3 on ratio of cationic to surfactant. As seen, only wh~n ratio of cationic tp s~urfaataaG reaches cmrtairi a~3,ai.:num ~.evel dose ,~p,oeitioa ei~ificauatiy increase .
to Thle p~seat invention relates to rd~.at~.vely low active bare (e. g., 50~ active. preferably lt$s than 40'x. ire praf~xably 3~x a~ less active? whe~in there is pree~eat s, relatively large acct of hYdxophilic structura_nt thY~'-~w ', ; .
stru0tutant and soap. if present. caaa~pxi~sas ao.~ors 15 tha,u about 20~ by wt, taorc than amo~t d# t~p~llo str~cturant) a,ad ~rhich further compriae~s. relatively la~s9s amount of oil/emallieaz (i.~.. at least ~~r~- t7riexpsctedly, tho applicants have discovered that when the =mtio og cmtioaie to suxfactax~t in such bare is ~qual to vx ale a' z p certain def fined rat io, t1~ dapoe it ion o f benef it agent f rom the ~ is =ecaarkahly eoh~oed. The cationic polymers u8~d must also have nli,nimum defined levels og charge density.
The box is described in greater deta~.l below : , _, , , .. . , . _ .
. _. __~_..,.....~.r.-=-~,..
..: : ~ ~---~-.-. -- . . .. _.-..--...._~- .- . .-,~.~.-... _...~.
. .._ . bars ,of the invention contain f~com about 10'~ to The ..
..S.O~r by wt.. mere: preferably 15 tc 40%. of a.~~syn~~tsc.
.._., soap s~fsctant. suitable surfactants are ga~rally selected from the group c4n9isti.ng of anionic, nonioo.iC, 30 amphoteric, xrwitcera.on.i.e asid~or cationic sux'factants a.nd rnixturee thereof such as are well knowzz iri the art.
AMENDED SHEET

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 (e. g., Cg-C22) sulfonate, primary alkane (e.g., Ce-C22) disulfonate, Cg-C22 alkene sulfonate, Cg-C22 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., C12-C18 alkyl sulfate) or alkyl ether sulfate (including alkyl glyceryl ether sulfates). Among the alkyl ether sulfates are those having the formula:
RO(CH2CH20)nS03M
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, e.g., C6-C22 sulfosuccinates); alkyl and acyl taurates, alkyl and acyl sarcosinates, sulfoacetates, Cg-C22 alkyl phosphates and phosphates, alkyl phosphate esters and alkoxyl alkyl phosphate esters, acyl lactates, Cg-C22 monoalkyl succinates and maleates, sulphoacetates, alkyl glucosides and acyl isethionates.
Sulfosuccinates may be monoalkyl sulfosuccinates having the formula:
R102CCH2CH(S03M)C02M; and amide-MEA sulfosuccinates of the formula R1CONHCH2CH202CCH2CH(S03M)C02M
wherein Rl ranges from Cg-C22 alkyl and M is a solubilizing cation.
Sarcosinates are generally indicated by the formula RCON(CH3)CH2C02M, wherein R ranges from Cg-C2p alkyl and M is a solubilizing cation.
Taurates are generally identified by formula wherein R2 ranges from Cg-C2p alkyl, R3 ranges from C1-C4 alkyl and M is a solubilizing cation.

.__ .._. ____ - _.. __ . .~~- ~- ~ . ~~-~.r . 0151Ei~1181_7~__ +4J 89 l:~s~4a.aa.~-~e 25-08-2000 ~ C ) ' ~ ~ EP 009905826 g _ particular~.y preferred are the Cg-Clg aryl isethianates.
These esters are prepared by reaction between alkali metal iseth:.onate with mixed aliphatic fatty acids having Pram 6 to 18 carbon atoms and an iodine value of less than 20. At least ?5% of Lhe mixed fatty acids have from 12 to 18 carbon moms and up to 25% have from 6 to 10 carbon atoms.
Acyl isethioxlates, when present, will range from about 10%
to about 50% by weight of the total bar composition.
Preferably, this component is present from about 20% to about 4Q%.
The acyl isethionate may be an alkoxylated isethionate such as is described in Mardi et al., U.S. Patent No. 5,393.466, hereby incorporated by reference.
Anionic surfaetaat may also be a "soap". 8y soap is meant alkali metal salts of aliphatic alkane- or alkene monocarbcxylic acids, more generally known as CIx-C~~ alkyl 2o fatty acids. Sodium and potassium salts are preferable. R
preferred soap is a mixture of about 15% to about 45%
coconut oil and about 55% to about B5% tallow.
The soaps may contain uneatLration in accordance with z5 commercially acceptable standards. Excessive uns2~turation is normally avoided.
The anionic component will comprise from about 10% to 50% of the bar cocrcposition.
AMENDED SHEET ; , . ~ ;

__ ..__ _.___ __ __ _ ~~~- d- v . ~1: y.t : UlSlEi_41_18J._7-~ - +49 8~3 2:~~l~la.a.~!~~* a 25-08-2000 ( C ) ' ' ~ E P 009905826 _ g _ Amphoteric detergents which may tie used in this invention include at lea9t one acid group. This riay he a carboxylic or a sulphonic acid group. They include quaternary nytrogen and therefore are quaternary amido acids. They should generally include an alkyl or a3kenyl group of ~ to 18 carbon atoms. They will usually comply with an overall structural forc~ula:
0 Rz ~.0 1f Rl - [-C-NH (CfIZ) n-1 m-N -X-Y
~3 where RZ is alkyl or alkenyl of 7 to 3.8 carbon atoms: R2 and R3 are each independently alkyl hydroxyalkyl or carboxyalkyl of 1 to 3 carbon atoms; n is 2 to 4; m is 0 to 1; x is alkylene of 1 to 3 carbon atoms optionally 2o substituted with hydroxyl, and y is -COZ or -SO~ .
Suitable amphoteric detergents within the above general formula include simple betainee of torrnula:

I
Ri N+- CH2C02_ I

and amido betainee of formula:
. . . AMENDED SHEET

.__ ____ __ __ _ ~~- ~- « : s 1: lg. : 01516411817-~ _ +49 89 23q94.4a.~:~ w 25-OS-2000 ( ~ ) ' ' ~ E P 009905826 - 1~ -Rx - CONFi ( C'rI21 m-;'I+° CH2 Cdr _ ~3 R
where m is 2 or 3.
In both formulae R1 is alkyl or alkenyl of ? to 18 carbons;
la and R2 and R~ are independently alkyl, hydroxyalkyl or carboxylalkyl of 1 to 3 carbons. R~' may,in partiCUlar be a .
mixture of C12 and C~~ alkyl groups derived from coconut so that at least half, preferably at least three duartere of the groups R~' have 14 to 14 carbon atoms. RZ a.nd R3 are preferably methyl.
A further possibility is that the amphoteric detergent is a sulphobetaine of fortriula:

i RI N+- (CH2~ 3503_ '3 R
or d- AMENDED SHEET

R1 -CONH(CH2)m N+- (CH2)3503_ where m is 2 or 3, or variants of these in which -(CH2)3503 is replaced by OH

In these formulae R1, R2 and R3 are as discussed for the amido betaine.
Amphoteric generally comprises 1% to 10% of the bar composition.
Other surfactants (i.e., nonionics, cationics) may also be optionally used although these generally would not comprise more than .O1 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 (C6-C22) phenols-ethylene oxide condensates, the condensation 15-11-2000 ' J54?3 ~~~ . .

roducts of aliphatic t~~Wls~ P=imaxy or secondaxY l5.near oz p d as coho~s with ethylene oxidr, as~d products nwlde by branche ion of athylerie tide with the reictioa products of cotZdeneat lease oxide sad ethy3saediatniae. Other so-CallCd propY
nonionic detrrgeat oQ'~ouads iaelude long chin tertiaity a exidesr long chain tertiary phoaphine oxides arid ataia dia11cy1 sulphoxidee, The noniowic ~aY a~eo be a sugar ~tn~ido, such as a 3. saccharide amide. Specifically. the surf~aotant rnay be po Y
one of the laacobiorrsmides described in u. S . pat~t No.
5 3 8 9 . Z'~ 9 to Au a t al - wh~.ch i S he~ebY i~clCCrpos'~ted bY
amide9 ~ttCh as described in U~$.
reference and pol'YhY~o~
ateax No. 5.31z~95e to l,~etton et al.. hereby incoxpo=~ted p into the suk~~ act ~epp~icat3,oa by refereroe ~
Exa las of catioxiic dstefgeats are the quataam~niucn eompounds such as alk~yldimothYlamn~or~v~m halogenidee .
p other svxfactants which may ba'~ed are described 3n 'U.s. .
. 3 Patent No. 3,~~~.3~s to parr~an Jr. assd °Surfa~ce 3~lctivm ants and Detergents" (Volume I ~ Iry ~x s~~wa=t~~ pe'~Y &

$erch, both s~f which sre a1$o incorporated into the subject . . _. _.. : .. ~ ypPl~.cation by refex'eace. .__.~. ~-~-,.~-__....._ -._. -- ----' .
Z5 osition comprises at least lC~:~acy1 " y ., .' A prsfet~d comp . .
is~ethionate arid 1~ to 1D~ betaine. . , .. . ' ~ co~o~d at the bar ~is hydxophilic '.
.. . ~ ~ ~ott,,er critic 30 structurant (e.3~. PolYalkylene glYGO1).
AMENDED SHEET

15-11-2000 . ~ ~ EP 009905826 ,64'13 I C y .. ' _~,.,......_......~.---~w~-.---40% p eg fly .._._...._. ,-------This com~nsrt comprises lQ; bY , .. . ' .
wt ,, of,.tho bas compomitica.' ' . , . ' .. .
3:5~ to 3'S~ .by .. ~ . . ~ . . , . .. . , The stz~a.cturarst has a~ nveltiag point of 40° ~to 100°C, preferably 45°C to 100°C. ~Dre Px~'~erably 50° to 90°C.
Generally these structure~nta vial be at lezst 10~ water soluble at roaee~ t~ern~psrature.
Mater~.als.which ate envisaged as the wt~ter salable xo structuxar_t tb) sire moderately high molecular weight polyalky7~eru~ oxides of .appropriate ansltiag point and in particular polyethylene glycols or en3.xrur~s thereof.
~olyethyl~ne glYcQls ~pEG's) which may be used rc~ay haves s molecular weight'in the re~nge 1,500-20,000.
xt should be uu~.eratood that each product t~e.g.~ '~nian Carbi.de's Caxbgwm~X~ ~1'EC-8.000) represents a distributior~ of rnalecular weights. Thus P~3G B,OOC, for exxample, has as 3o average MW range:of ?.o0d-9.oao, wh~.ls pEC3 30o hac as , average M91 raage.f~'om 285 to 315. The av~xage MW of the product can be arch~re between the low and high value. sad ther~ may still be a good portion of the material with MW
below the 3.ow vmlue end above the high vela~.

In socae embodiments of this invention ~.L is preferred t°
include a fairly~smal3. quaatiCy of polyalkylerie glycol polyethylene glYcnll with a iruoleeular weight Zn the range frc~n 50, 000 to 500, 000, especially m4lecu:.a= we~.ghts . 30 of around =C0,00o. Such polyethylene glycols ha'~ boer~
AMENDED SHEET

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 5%, 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 (b) 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°C and' may be used as part or all of the water soluble structurant (b). 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 - CA 02340706 2001-02-15 U1~1~1181~-i _.. +ø9 8~J 2:.3~J94-'i~65:ayi() 25-08-2000 ~~~ ~ ~ ' EP 009905826 structurant, Among these, for example, are included maltodextrin anal similar water soluble starches. If included, these adjuvants would comprise no mare than about 10% by urt. of the composition.
The water insoluble structurants are also required to have a meltixu3 point in the range 4~-20o°C, more preferably at least 50°C, notably 50°C to 9Q°C. Suitable materials which are particularly envisaged are fatty acids, particularly those 1D having a carbon chain of 12 to 24 carbon atoms. Examples are laurie, myristic, palrnitic, stearic, araahidonic 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 alkanois of 8 to 20 carbon atoms, particularly cetyl alcohol. These materials generally have a water solubility of less than Sgjlitre at 20°C.

The relative proportions of the water soluble structurants and water insoluble etructurants govern the rate at which the bar wears during use. The presence of the water insoluble stxucturant tends to delay dissolution of the bar when exposed to v~ater during use and hence retard the rate of wear .
In genera7~, insoluble etructurant will comprise S to 20% by wt . of the cocrcpos it ien .
. .
'~ ~ ~ ~ '~ "'~'' AMENDED SHEET ~ ''~-'"'=~ ~-'' Js4~~l~.
-__ YlLiOTi ,~t 0~~, ate= ~T~a11~1b1~
. .. ~ACCOrd~.n_e3 t_o _t_he in~~ ..._~.::.~ ...., . ,:;. ~ - _ _ __: _ .
~'s~;v~c~artant (c) dooa not exc~esd the am4unt o~ liydzaphil'ic . ~ ,:
w et~eturant (bl plus arty sox whidh may ;be , ~ewe;,nt.. ~i:.~ore~.~ . ._ ..
.
.. . _ .. . ~ . : ~. . . , . ~ ut 10 i ~ b~' ~ Whil a not wi sh i~g a o ~~'be bound ~bY
wt.
theory, thi~ is believed to be so bsaause wh$ri these is too ernsch soap a~ndlor hy~ph~~Zia stxuctu~~t~ level og $epoaitioa is reduced.
Thw beatfit agent of the compooiti~ss of the invention is ~.neluded in the co~apos3t3.or~s to moisturize, condition a~nd/ax protect the skin. 8y nbenefit agent" is meant a subata~nce that softens the skin (stratuan corneum) ark ke4p$ it soft by retarding the deCt'eass of its water content and.lcr Protects the skin.
greferxed benefit agents i~clud4:
(a) silicone oils. gums awd modifia'tiatss thereof such as ~,i~~ ~d cyclio polydime~thylsiloxanes, amine. alkyl alkylaryl and as~Y1 silicone oils:
tb) fats sad oils inc7.udirig riatuxal fists arid oils suoh ds jojoba, Soar"bests. sunflower, r~.co 'bran., nv~ocado, almond.
olive. ~sa~. persic, castor. oocon~t. rni~ oils cacsa fat. beef tallow ls=dt ~den~ oils obtsiaed by hydrogsr~ting thQ aforrrnentionad oils; and synthetic mono.
di and triglyceridss such is myristie acid glyCeride and 2-ethylhexanoic acid glyceride~
woes sv.ch ass cattZauba, sp~zma ceti, beeswax. l~vl in and dezivati.ve~a . t)iereo~:
(d) hydrophobic plant eXzratts;
AMENDED SHEET

(e) hydrocarbons such as liquid paraffins, petroleum jelly, microcrystalline wax, ceresin, squalene, squalane, and mineral oil;
(f) higher fatty acids such as lauric, myristic, palmitic, stearic, behenic, oleic, linoleic linolenic, lanolic, isostearic and poly unsaturated fatty acids (PUFA) acids;
(g) higher alcohols such as lauryl, cetyl, steryl, oleyl, behenyl, cholesterol and 2-hexadecanol alcohol;
(h) 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;
(i) 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;
(j) lipids such as cholesterol, ceramides, sucrose esters and pseudo-ceramides as described in European Patent application No. 556,957;
(k) vitamins such as vitamin A and E, and vitamin alkyl esters, including those vitamin C alkyl esters;
(1) sunscreens such as octyl methoxyl cinnamate (Parsol MCX) and butyl methoxy benzoylmethane (Parsol 1789);
(m) phospholipids;

(n) humectants such as glycerin, propylene glycol and sorbitol; and (o) 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 fox 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 00/12b70 PCT/EP99/05826 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 anti-viral 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 m-toluamide (DEET); and mixtures thereof.
The benefit agent comprises 2 to 40°s, preferably 5 to 20~s 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.
Thus, for example, a Jaguar~R~ type cationic such as Jaguar C14S~R~ (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~R~) which has charge density of 0.00661. By contrast, dimethyldiallylammonium chloride (Mirquat 100~R~) has density of 0.00793 and is within the invention.

..__ ____ -__ __ ._ ~~- o- a ~ 11:15 : O1_516~1I81_7-->__.. +49 8q ~.'wQ.'~~c~r."..

25-08-2000 (~) ~ ~ ~ ' It is also important fax the cationic polymer to be (a?
fully hydrated prior to incorporation in the bar formu'_ation and (b) at a concentration of 1% by wt. or higher for the desired benefit, i.e., enhanced deposition. The coctm:ercial application (usefulness) of the said invention would therefore require the cationic polymer to be at a relatively high concentration when hydrated to avoid the impracticality, difficulty and high costs of drying the syndet bar øormulation. A cationic polymer such as dimethyldiallylammonium chloride (1'radename Mirquat 100? can be prepared at concentrations of 40% (60% water), whereas the low charge density quaternized guar cationic polymer (Tradename Jaguar Cl4s) exemplified by Kacher et al. can only be prepared at concentrations of approximately 3% (9'I%
water) and are nat practical on a commercial scale.
Exemplary cationic polymers which may be used according to the invention include Salcare~ type pclymers from Allied Colloids, and Merquat~ type polymers from Calgon.
Those cationic polymers Which are generally net applicab~.e according to the invention are the high molecular weight, love charge density polymers such as Polymer JR-4oG~° frarn Amerchol azid cationic polysaccharides of the cationic guar gum clas9 such as Jaguar C14S~ from Rhone-Poulenc.
Tt is an important aspect of the invention that there be a minimum amount of cationic polymer be used. The ratio of cationic to surfactant is 0.06:2 to l:l, more preferably 0.08 to 1 to 0.5 tv 1.
AMENDED SHEET

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.
~'Y~1MDT.~Q
MATERIALS AND METHODS
M~f-cri ~l o Sodium cocoyl isethionate was supplied by Lever Baltimore, Polyethylene glycol (PEG 8000) was supplied by Union 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 90°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 (~5%), 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.

The nose cone of the plodder was heated to 45-50°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 (e. g., polydimethylsiloxane) into Dove~R~ -like compositions (e. g., high acyl isethionate bars structured with fatty acid) or primarily soap based compositions results in negligible deposition of the benefit agent. High surfactant levels (e. g., 60~) and insoluble structurants (e. g., 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.

Component Ex. Ex. Ex. Ex. 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 4.0 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 8.0 Na Stearate 5.0 5.0 5.0 5.0 5.0 CAP Betaine 5.0 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 4.0 PEG 540 5.0 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-1 and 835cm 1. This is plotted on a standard curve and the deposition value in ug/cm2 is reported.

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 3.0 9.4 7.4 17 0.114 .25 Ex. 5 _ 4.0 ~ 11.3 9.3 ~19 0.133 30.0 ~

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 poiymer:surfactant ratio is increased, a considerable increase in deposition is observed.
The following formulations were selected for further deposition.

Component: Ex. 6 Ex. 7 Ex. 8 (Body Wash) Na Cocoyl Isethionate 30.0 40.0 6.5 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 5.0 Palmitic-Stearic Acid 14.0 14.0 0 Na Laureth Sulfate 0 0 6.5 CAP Betaine 5.0 5.0 5.6 Lauro Amphoacetate 0 0 5.6 Isostearic Acid 0 0 5.0 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 2.5~ 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:

Table Experiment # Deposition ~g/cm2 Ex. 6 - -14.5 +/-- -10.3-Ex. 7 17.2 +/- 9.5 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 8). As noted, significantly higher levels of oil are deposited on the skin from the bar prototypes.

Claims (11)

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1. A bar composition comprising:
(a) 10% to 50% by wt. synthetic non-soap surfactant selected from tho group consisting of anionic.
nonionic, cationic, amphoteric/zwitterionic surfactants and mixtures thereof;
(b) 10% to 40% by wt. of a hydrophilic structurant having a melting point in the songs 40° to 100°C;
(c) 53 to 20% by wt. of a water insoluble structurant with MF 40° to 200°C;
(d) 2% to 40%~ of a benefit agent that softens the skin and keeps it soft by retarding the decrease of its water content and/or protects the skin;
(e) 1.0% to 10% by wt. cationic polymer having a molecular weight of from 1000 to 2,000,000 Daltons:
wherein the amount of insoluble structurant (c) and soap; if any, exceeds amount of hydrophilic structurant (b) by no store than 10% by wt. of total bar composition: and wherein the amount of cationic polymer (e) is such that ratio of cationic polymer to surfactant is 0.06:1 to 1:1; and wherein charge density of cationic polymer is greater than 0,0.07; and wherein the ratio of hydrophilic to hydrophobic structurant is at least 1:2.

2. A composition according to claim 1, wherein surfactant is an anionic surfactant.

3, A composition according to claim 2, wherein surfactant is acyl isethionate or alkali metal alkyl ether sulfate.

4. A composition according to any of the preceding claims, comprising 15 to 40% by wt. (a).

5. A composition according to any of the preceding claims, comprising 15 to 3~% by wt. (b).

6. A composition according to any of the preceding claims, wherein the hydrophilic structurant (b) is at least 10%
water soluble at room temperature.

7. A composition according to any of the preceding claims, wherein the hydrophilic structurant (b) is selected from.
polyalkylene oxides having MW 1500 to 20,000 and block copolymers of polyethylene and polypropylene oxide, and mixtures thereof.

8. A composition according to any of the preceding claims, wherein the insoluble structurant (c) is C12 to C24 fatty acid.

9. A composition according to any of the preceding claims, wherein the benefit agent (d) comprises 5 to 20% by wt. of the composition.

10. A composition according to any of the preceding claims, comprising 1.0% to 7% cationic polymer.

11. A composition according to any of the preceding claims, wherein the ratio of cationic to surfactant is in the region 0.08:1 to 0.5 to 1.