CA2242932A1 - Shampoo compositions with improved deposition of antimicrobial agents - Google Patents

Abstract

Disclosed are antidandruff shampoo compositions with improved deposition of antimicrobial agents, which compositions comprise (a) from about 7 % to about 30 % by weight of a detersive surfactant selected from the group consisting of anionic surfactant, amphoteric surfactant, zwitterionic surfactant, and combinations thereof; (b) from about 0.1 % to about 10 % by weight of an antimicrobial agent; (c) from about 0.5 % to about 10 % by weight of a suspending agent; (d) from about 0.01 % to about 1.0 % by weight of a cationic guar polymer having a charge density of from about 0.01 meq/g to about 3 meq/gm; and (e) from about 40 % to about 92 % by weight of water; wherein at least about 50 % by weight of the cationic guar polymer is in coacervate form, said coacervate comprising detersive surfactant and cationic guar polymer.

Description

W O 97/26854 PCTrUS97100081 SHAMPOO COMPOSITIONS WITH IMPROVED
DEPOSITION OF ANTIMICROBL~L AGENTS

FIELD OF T~IE INVENTION
The present invention relates to shampoo compositions containing antimicrobial agents which provide antidandruff activity. In particular, the present invention relates to shampoo compositions containing antimicrobial agents, preferably particulate antimicrobial agents, in combination with a cationic guarpolymer as an antimicrobial agent deposition aid.

BACKGROUND OF T~IE I~VENTION
Various anti-dandruff shampoo compositions are commercially available or otherwise known in the shampoo art. These compositions typically comprise particulate, crystalline antimicrobial agents dispersed and suspended throughout the composition. Antimicrobial agents used for this purpose include sulfur, seleniumsulfide and heavy metal salts of pyridinethione During the shampooing process, these antimicrobial agents deposit on the scalp to provide anti-dandruffactivity.
Many anti-dandruff shampoos, however, do no provide sufficient antimicrobial agent deposition during the shampooing process. Without such deposition, the antimicrobial agents simply rinse away during shampooing and the.erore provide little or no anti-dandruff activity. In addition, the detersive surf. ~t~nt.c in these shampoo compositions which are designed to remove oil, grease, dirt, and particulate matter will also carry away particulate antimicrobial agents during nnsing, thus further decreasing deposition and anti-dandmff activity.
Depos;liQn of particulate antimicrobial agents is especi~lly difficult in anti-dandn~ff sharnpoo compositions co.~ g crystalline suspendin~ agents. These sl:~çncl;~g agents help dis,~-~e and suspend particulate antimiGrobial agents in the shampoo composition. These suspending agents, however, adversely affect lathering p~.rGl--,ance. It has thcr~,fore bccol,-e conventional practice to enh~nce the lathering pe. ro"~ance of these sLIIIpoos by increasing detersive surfactant concentrations or by adding foam boosters, both of which further decrease deposition of particulate antimicrobial agents from the shampoo compositions.
~ t has now been found that select cationic deposition polymers are especially effective in providing enhanced deposition of antimicrobial agents, especially particulate antimicrobial agents, from a shampoo composition. The select polymers W O 97/26854 PCTrUS97/00081 are cationic derivatives of guar gum which have been found to be most effective when used in combination with c~stalline suspending agents and high levels of anionic, amphoteric or zwitterionic surfactant in an anti-dandruff shampoo composition .
It is therefore an object of the present invention to provide an anti-dandn~ff shampoo composition with improved deposition of antimicrobial agents, especiallyparticulate antimicrobial agents, and further to provide for such improved deposition in the presence of crystalline suspending agents and high concentrations of detersive surfactant. It is yet another object of the present invention to provide anti-dandru~
shampoo compositions with excellent anti-dandruff activity and reduced concentration of antimicrobial agents.

SUMMARY OF THE INVENTION
The present invention is directed to high lathering, anti-dandruff shampoo compositions with improved deposition of antimicrobial agents, which compositions comprise (a) from about 7% to about 30% by wei~ht of a detersive surfactant selected from the group consisting of anionic surfactant, amphoteric surfactant,zwitterionic surfactant, and combinations thereof; (b) from about 0.1% to about 10%
by weight of an ~ntin~jcrobial agent; (c) from about 0.5% to about 10% by weight of a suspending agent; (d) from about O.Ol~/o to about 1.0% by weight of a cationicguar polymer having a charge density of from about 0.1 to about 3meq/gm, and (e)from about 40% to about 92% by weight of watcr, wherein at least about 50% by weight of the cationic ~uar polymer is in coacervate forrn, said coacervate comprising detersive surfactant and cationic guar polymer.
.

DETAILED DESCRIPTION OF THE INVENTION
The sl,~,.~)oo compositions of the present invention can comprise, consist of, or consist e~se~ y of thc ess~n~ ek .,~ and limitations of the invention des~,~ibcd hcrein, as well any of the additional or optional ing~l;enls, cornponents, or limitations described herein.
All pcrc~ g~s, parts and ratios are based upon the total weight of the shampoo compositions of the present invention, unless otherwise s~,eciLcd. All such weights as they pertain to listed ingredients are based on the active level and,therefore, do not include carriers or by-products that may be included in co,..me.c;ally available materials.

CA 02242932 l998-07-l4 W O 971268~4 PCT~US97/00081 Detersive Surfactant The shampoo compositions of the present invention comprise a detersive surfactant selected from the group consisting of anionic surfactants, amphotericsurfactants, zwitterionic surfactants, and combinations thereof. The shampoo compositions preferably comprise an anionic surfactant. The detersive surfactantprovides the shampoo compositions with cleaning performance Anionic surfactant The detersive surfactant component of the shampoo compositions is preferably an anionic surfactant. Concentrations of anionic surfactant can range from about 7% to about 30%, preferably from about 10% to about 25%, more preferably from about 12% to about 22%, by weight of the shampoo compositions.
Anionic surfactants for use in the shampoo compositions include alkyl and alkyl ether sulfates. These materials have the respective formulae ROS03M and RO(C2H40)xSO3M, wherein R is alkyl or alkenyl of from about 8 to about 30 carbon atoms, x is an integer from I to 10. and M is a hydrogen, alkali metal (e.g., lithium, sodium. potassiun~), alkali earth mctal (e.g., beryllium, magnesium, calcium, strontium, barium) amrnonium or substituted arnr-loni~
Plefc.~bly, R has from about 10 to about 18 carbon atoms in both the alkyl and alkyl ether sulfates. The alkyl ether sulfates are typically made as condensation products of ethylene oxide and monohydric alcohols having from about 8 to about 24 carbon atoms. The alcohols can be derived from fats, e.g., coconut oil or tallow, or can be synthetic. Lauryl alcohol and straight chain alcohols derived from coconut oil are p-~f~ d. Such alcohols are reacted with between about O and about 10, and es,~ -'ly about 3, molar proportions of ethylene oxide and the resulting mixture of I o'ecl~lar species having, for e~ nl-le, an average of 3 moles of ethylene oxide per molc of alcohol, is sulf7t~d and neutralized.
Specific e~ p'~~ of alkyl ether sulfates which msy be used in the shampoo cGmpos;lions of the present invention are sodium and am",or Im salts of coconut alkyl triethylene glycol ether sulfate; tallow alkyl tricthylene glycol ether sulfate, and tallow alkyl hexaoxyethylene sulfate. Highly prefe.~cd alkyl ether sulfates are those co,np.-s,ng a combination of individual compounds, the combination having an average alkyl chain length of from about 10 to about 16 carbon atoms and an average degree of ethoxylation of from about I to about 4 moles of ethylene oxide Other suitable anionic surf;lct~ntc are the water-soluble salts of organic, sulfuric acid reaction products of the general forrnula [ Rl-S03-M ] where Rl is W O 97/26854 PCT~US97/00081 selected from the group consisting of a straight or branched chain. saturated aliphatic hydrocarbon radicals having from about 8 to about 24, preferably about 10 to about 18, carbon atoms; and M hydrogen, alkali metal (e.g., lithium, sodium, potassium), alkali earth metal (e.g.~ beryllium, magnesium, calcium, strontium, barium) ammonium or substituted ammonium. Examples of such surfactants are the salts of an organic sulfuric acid reaction product of a hydrocarbon of the methane series, inciuding iso-, neo-, and n-paraffins, having about 8 to about 24 carbon atoms, preferably about 12 to about 18 carbon atoms and a sulfonating agent, e.g., SO3,H~SO4, obtained according to known sulfonation methods, including bleaching and hydrolysis. Preferred are alkali meeal and ammonium sulfonated C10 18 n-paraffins.
Still other suitable anionic surf~ct~ntc. are the reaction products of fatty acids esterified with isethionic acid and neutralized with sodium hydroxide where, forexample, the fatty acids are derived from coconut oil; sodium or potassium salts of fatty acid amides of methyl tauride in which the fatty acids, for example, are derived from coconut oil. Other similar anionic surfactants are described in U.S. Patent2,486,921, U.S. Patent 2~486,922; and U.S. Patent 2,396,278, which descriptions are incorporated herein by reference.
Other anionic surf~ct~lts suitable for use in the shampoo compositions are the succinnates, examples of which include disodium N-octadecylsulfosuccinn~te;
cliso~ m lauryl sulfoslucc~ e; ~ "~o~ ~ lauryl sulfosuccin~te; tetrasodium N-( 1,2-dicarbox,vethyl)-N-octadecyisl~lfosuc~-innste; diamyl ester of sodium sulfosl~ccinic acid; dihexyl ester of sodium su1fosuccinic acid; and dioctyl esters of sodium sulfosuccinic acid.
Other suitable anionic surfa~nts include olefin sulfonates having about 10 to about 24 carbon atoms. The term "olefin sulfonates" is used herein to mean co~l~po~Jn~s which can be produced by the sulfonation of alpha-olefins by means of unc~mr~lexed sulfur trioxide, followed by neutrali7~ion of the acid reaction mixture in conAi~ionc such that any sulfones which have becn formed in the reaction are hydrolyzed to give the co,l.,tl)on~lin~ hydroxy-alkanesulfonates. The sulfur trioxide can be liquit or gwous, and is usually, but not necessarily, diluted by inert dilnents7 for example by liquid S02, chlolindl¢d hydr~ca.l,ons, etc., when used in the liquid form, or by air, nitrogen, gaQCOUS S02, etc., when used in the g~C~ous form.
The alpha-olefins from which the olcfin sulfonates are derived from mono-olefins having from about 12 to about 24 carbon atoms, plef~lably from about 14 to about 16 carbon atoms. Straight chain olefins are p,ef~ ,d.
In addition to the tnJe alkene sulfonates and a proportion of hydroxy-alk~n~su~fonates, the olefin sulron~i~es can contain m~nor amounts of other WO 97126854 PCT~US97/00081 -materials, such as alkene disulf~nates dependin~ upon the reaction conditions~
proportion of reactants, the nature of the starting olefins and impurities in the olefin stock and side reactions during the sulfonation process A specific alpha-olefin sulfonate mixture of the above type is described more fully in the U.S Patent 3,332,880~ which description is incorporated herein by reference.
Another class of anionic surfactants suitable for use in the shampoo compositions are the beta-alkyloxy alkane sulfonates. These compounds can be represented by the formula:
o~2 H
R'--C--C--SO3M

where Rl is a straight chain alkyl group having from about 6 to about ~0 carbon atoms, R2 is a lower alkyl group having from about I (preferred) to about 3 carbon atoms, and M hydrogen, alkali metal (e.g., lithium, sodium, potassium), alkali earth metal (e.g., beryllium, magnesium, calcium, strontium, barium) ammonium or substituted ammonium.
Many other anionic surfactants suitable for use in the shampoo compositions are described in McCutcheon's. Frnulsifiers and Dctergents. 1989 Annual, published by M. C. Publishing Co., and in U.S. Patent 3,929,678, which descriptions are incol ~GI ated herein by reference.
Pl~fe.le~ anionic surfactants for use in the shampoo compositions include ammonium lauryl sulfate, ~mmoni--m Iaureth sulfate, triethylamine lauryl sulfate, tri-ethylamine laureth sulfate, triethanolam;ne lauryl sulfate, triethanolamine laureth sulfate, ~I~onoe~banola~-l;ne lauryl sulfate, monoethanolamine laureth sulfate, diethanolamine lauryl sulfate, diethanolamine laureth sulfate, lauric monoglyceride sodium sul&te, sodium lauryl sulfate, sodium laureth sulfate, potassium lauryl sulfate, potassium laureth sulfate, sodium lauryl sarcGsn)ate, sodium lauroyl sarcosinate, lauryl sar~,~~:lle, cocoyl jal c03ine, ammonium cocoyl sulfate, a~nrno~ium lauroyl sulfate, sodium cocoyl sulfate, sodium lauroyl sulfate, potassium cocoyl sulfate, potassium lauryl sulfate, monoethanolamine cocoyl sulfate, monoethanolamine lauryl sulfate, sodium tridecyl benzene sulfonate, sodium dodecyl be..7ene sulfonate and co..lb; ~~ions thereof.

Amphoteric and zwitterionic surf~ct~ntc The detersive surfactant co"lpon~nl of the shampoo compositions may comprise an amphoteric and/or zwitterionic surfactant. Concentrations of such surfactams can range from about 0 5% to about 20~~o~ pref'erably from about 1~/otO
about 1 0~~o~ by weight of the shampoo compositions.
Arnphoteric surfactants for use in the shampoo compositions include the derivatives of aliphatic secondary and tertiary amines in which the aliphatic radical is straight or branched and one of the aliphatic substituents contains from about 8 to about 1~ carbon atoms and one contains an anionic water solubilizing group, e g.carboxy, sulfonate, sulfate, phosphate, or phosphonate.
Zwitterionic surfactants for use in the shampoo compositions include the derivatives of aliphatic quaternary ammonium, phosphonium, and sulfonium compounds, in which the aliphatic radicals are straight or branched, and wherein one of the aliphatic substituents contains from about ~ to about 18 carbon atoms and one contains an anionic group, e.g., carboxy, sulfonate~ sulfate, phosphate, or phos-phonate. These compounds can be represented by the forrnula:
(R3~

where R contains an alkyl, alkenyl, or hydroxy alkyl radical of from about 8 to about 18 carbon atoms, from 0 to about }0 ethylene oxide moieties and from 0 to about I glyceryl moiety; Y is selected from the group consisting of nitrogen, phosphorus, and sulfur atoms; R3 is an alkyl or monohydroxyalkyl group containing about 1 to about 3 carbon atoms; X is I when Y is a sulfur atom, and 2 when Y is a nitrogen or phosphorus atom; R4 is an alkylene or hydroxyalkylene offrom about 1 to about 4 carbon atoms and Z is a radical selected from the group consisting of carboxylate, sulfonate, sulfate, phosphon~te, and phosphate groups.
Ex~nples of amphoteric and zwitterionic surfactants also include sultaines and ~idos~ltaines. Sultaines and ~idos~lt~ ec can be used as foam enhancing surfactants that are mild to the eye in partial replacement of anionic surf~ct~nts.
Sultaincs, including arnidosultaines, include for eY~Inrle7 cocod;~ I hylpr~)yls,Jltaine, stearyldimethylpropylsultaine, lauryl-bis-(2-hydroxyethyl) propylsultaine and the like; and the arnidosultainessuch as coco~midod..,.elhylpropylsultaine, stearylarnidododimethylpropylsultaine, laurylarnidobis42-hydroxyethyl) propylsultaine, and the like. Preferred are amidohydroxysultaines such as the C12-C18 hydrocarbyl amidopropyl hydroxy-sultaines, especially C12-C14 hydrocarbyl amido propyl hydroxysultaines, e.g., laurylamidopropyl hydroxysultaine and cocamidopropyl hydroxysultaine. Other sultaines are des_-ibed in U.S. Patent 3,950,417, which dcsc-;ptions are incor-porated herein by l.,fe.cnce.

?

Other suitable amphoteric surfactants are the aminoalkanoates of the formula R-NH(CH2)nCOO~f~ the imlnodialkanoates of the formula R-N[(CH2)mCOoM]2 and mixtures thereof; wherein n and m are integers from I to 4, R is C8 - C~2 alkyl or alkenyl, and M is hydrogen, alkali metal, alkaline earth metal, ammonium or alkanolammonium Examples of suitable aminoalkanoates include n-alkylamino-propionates and n-alkyliminodipropionates, specific examples of which include N-lauryl--beta-amino propionic acid or salts thereof, and N-lauryl-beta-imino-dipropionicacid or salts thereof, and mixtures thereof Other suitable amphoteric surfactants include those represented by the t'ormula:

R'CON- (CH2)n ~--CH2Z

where Rl is alkyl or alkenyl having from about 8 to about 22 carbon atoms, preferably from about 12 to about 16 carbon atoms, R2 is hydrogen or CH2CO2M; R3 is CH2CH20H or CH2CH20CH2CH2COOM; R4 is hydrogen, CH2CH20H, or CH2CH20CH2CH2COOM, Z is CO2M or CH2CO2M; n is the integer 2 or 3, preferably 2; M is a hydrogen, alkali metal (e.g., lithium, sodium, potassium), alkali earth metal (e.g., beryllium".,agl~es;um, calcium, strontium,barium) arnmonium or substituted ammonium.
This type of surfactant is so.~ .,es çl~csified as an imidazoline-type amphoteric surfactant, although it does not nece,~ -- ily have to be derived, directly or indirectly, through an imi~ e intermediate.
S~ le materials of this type are marketed under the trade name MIRANOL and are understood to co-"pli~e a col rl~ mixture of species, and can exist in protonated and non-protQn~d species dep~ndi~lg upon pH with respect to species that can have a hydrogen at R2. All such variations and species are meant to be e--co l.pqcsed by the above formula.
Examples of surf~~t~ntc of thc above formula are monocarboxylates and dicarboxylates. Exa.~.ples of these materials include cocoamphocarboxypropionate, cocoamphocarboxypropionic acid, cocoamphocarboxyglycinate (alternately l~f~ d to as cocoampho~i~cetA~e), and cocoampho~cet~te.
Commercial amphoteric surf~çt~ntc include those sold under the trade names MIRANOL C2M CONC. N.P., MIRANOL C2M CONC. O.P., W O 97J26854 PCTrUS97/00081 .~fIRANOL C2M SF~ MIRANOL CM SPECIAL ~Miranol, ~nc ); AlKATERIC
2CIB (Allcaril Chemicals), AMPHOTERGE W-2 (Lonza, Inc.), MONATERIC
CDX-38, MOI~iATERIC CSH-32 (Mona Industries), REWOTERIC AM-2C
(Rewo Chemical Group), and SCHERCOTERIC MS-2 (Scher Chemicals) Betaine surfactants (zwitterionic) suitable f~r use in the shampoo compositions are those represented by the formula:

Il l I
Rs--C--N-(CH2)~ N--Y--R' ~3 n where Rl is COOM or CH(OH)CH2SO3M
R2 is lower alkyl or hydroxyalkyl;
R3 is lower alkyl or hydroxyalkyl, R4 is a member selected from the group consisting of hydrogen and lower alkyl;
R5 is higher alkyl or alkenyl;
Y is lower alkyl, preferably methyl;
m is an integer from 2 to 7, pref~. ably from 2 to 3, n is the integer I or 0; and M is a hydrogen, alkali metal, alkali earth metal, ammonium or substituted ammonlum.
As used in this context, the terrn ''lower alkyl" or "hydroxyalkyl" means straight or branch ch~ined saturated, aliphatic hydrocarbon radicals and substituted hydrocarbon radicals ha~ing from one to about three carbon atoms such as, for eAa~ le, mcthyl, ethyl, propyl, isopr~pyl, hydroxypropyl, hydroxyethyl, and the like. The term "higher alkyl or alkenyl" means straight or branch chained satu-rated (i.e., "higher alkyl") and unsaturated (i.e., "higher alkenyl") aliphatic hytrocarbon raticals having from about eight to about 20 carbon atoms such as, for exarnple, lauryl, cetyl, stearyl, oleyl, and the like. lt should be understood that the term "higher alkyl or alkenyl" includes mixtures of radicals which may contain one or more inte....eA;~te lin~s such as ether or polyether linkages or non-functional substit~terlts such as hydroxyl or halogen radicals wherein the radical remains of hydrophobic character.
Examples of suitable surfactant betaines of the above fonmula wherein n i zero include the alkylbetaines such as cocodimethylcarboxymethylbetaine, lauryldimethylcarboxymethylbetaine, lauryl dimethyl-alpha-carboxyethylbet~ine.
cetyldimethylcarboxymethylbet~in~, lauryl-bis-(2-hydroxyethyl)carboxymethyl-W O 971268~4 PCTAUS97/00081 bet~ine, stearyi-bis-(2-hydroxypropyl)carboxymethyibetaine, oleyl-dimethyl-gamma-carboxypropylbetaine, lauryl-bis-(2-hydroxypropyl)-alpha-carboxyethylbetaine, etc. Suitable sulfobetaines include cocodimethylsulfopropyl-betaine, stearyldimethylsulfopropylbetaine, and lauryl-bis-(2-hydro~cyethyl)sulfopropylbetaine.
Suitable amido betaines and amidosulfo betaines for use in the shampoo compositions includ~ the arnidocarboxybetaines, such as cocoamidodimethy}carboxymethylbetaine, laurylamidodi-methylcarboxymethylbetaine~ cetylamidodimethylcarboxymethylbetaine, laurylamido-bis-(2-hydroxyethyl)-carboxymethylbetaine, cocoamido-bis-(2-hydroxyethyl)-carboxymethylbetaine, etc. ~nido sulfobetaines include cocoamidodimethylsulfopropylbetaine, stearylamidodimethylsulfo~ropylbetaine, and lauryl-amido-bis-(2-hydroxyethyl)-sulfopropylbetaine.

Highly solubilizin~ surfactants The shampoo compositions of the present invention are preferably ~ee of highly solubilizing surf~ct~nt~ such as N-acyl amino acid surf~ct~ntc As used in this context, "substantially free" means that the shampoo con"~os;lions preferably contain no more than about 1%, more preferably no more than about 0.5%, even more preferably no more than about 0.25%, most preferably eSsent~ y zero percent, of highly solubilizing surfactants by weight of the shampoo compositions Less preferably, the shampoo compositions may co~ ..se N-acyl amino acid surfactants as a secondary optional surfactant or as the detersive surfactant co~ orP .~ ofthe shampoo compositions.
N-acyl amino acid surfactants are well known surfnct~nts for use in a variety of products. A desc,;ylion of these surf~ct~ntc and their synthesis can be found, for example, in Anionic Suractants. Part II. Surfactant Science Scries. Vol. III. edited by Warner M. I.i-.fi~ld7 Marcel DekJcer, Inc. (New York and Basel), pp ~81-617 (1976), which description is il~co.yol~ted herein by ,~,f. rence.
Suitable N-acyl amino acid surfact~nts for use in the shampoo compositions herein inctude N-acyl hydrocarbyl acids and salts thereof, which can be ,epresenled by the formula:

W O 97/268S4 PCTrUS97/00081 1() Rl--C N [ R3~COOM

wherein Rl is a alkyl or alkenyl radical having from about 8 to about 24 car~on atoms, preferably from about 12 to about 18 carbons atoms; R2 is hydrogen, alkylhaving from about I to about 4 carbon atoms, phenyl, or CH2COOMl preferably alkyl having from about I to about 4 carbon atoms~ more preferably alkyl having from about I to about 2 carbon atoms; R3 is (CR4)2 or alkoxy having from about Ior about 2 carbon atoms, wherein each R4 is independently hydrogen or alkyl having from about I to about 6 carbon atoms or alkylester thereof; n is an integer from I to 4, preferably I or 2; and M a hydrogen, alkali metal (e.g., lithium, sodium, potassium), alkali earth metal (e.g., berylliuml magnesium, calcium, strontium, barium) ammonium or substituted ammonium. Especially prefe~, ed are N-acyl sarcosinates and acids thereofl examples of which include lauroyl sarcosinatel myristoyl sarcosinatel cocoyl sarcosinate, and oleoyl sarcosinate, preferably assodium or potassium salts.
It has been found that the highly solubilizing surfactants described hereinabove, when used in combination with the guar cationic poiymers described hereinafterl are less effective in providing improved deposition of the antimicrobial agent of the shampoo compositions herein. It has also been found that, by increasing the cationic charge density of the guar cationic polymer in the presence of these highly solubilizing surfactant, the less effective antimicrobial agent deposition can be improved substantially. In the presence of the highly solubilizing surfactants in the shampoo compositions herein. Il.c.er~re, the cationic guar polyrner should have a cationic charge density of from about O.9meq/g to about 4meqJg, p,~f~. ably between about 1.0 and 3meq/g.
Antin~icrobial ~Pent The shampoo compositions of the present invention comprise a safe and effective amount of an antimicrobial agent. The antimicrobial aBent provides theshampoo compositions with antimicrobial activity. The antimicrobial agent is preferably a crystalline particulate that is insoluble in, and d;sp.,.~ed throughout, the shampoo. compositions. Effective concentrations of such ~ntimicrobial agents generally range from about 0.1% to about 5%, more pr~ bly from about 0.3% to about 5%, by weight of the shampoo compositions. Suitable ~ robial agents include sulfur, octopirox, selenium sulfide, and pyridinethione salts.
Selenium sulfide is a pref~;lred particulate antimicrobial agent for use in the shampoo compositions, effective concentrations of which range from about 0.1% to W O 97/26854 PCT~US97/00081 Il about 5 0~O, pret'erably t'rom about 0.3% to about 2 ~~O, more preferably from about 0 5% to about 1.5~/0~ by weight of the shampoo compositions Selenium sulfide is generally regarded as a compound having one mole of selenium and two moles of sulfilr, although it may also be a cyclic structure, SexSy, wherein x + y = 8. A~erage particle diameters for the selenium sulfide (selenium disulfide) are less than 15um~
preferably less than 10 um, as measured by forward laser light scattering device~ e.g., Malvern 3600 instrument. Selenium sulfide compounds are well known in the shampoo art~ and are described, for example in U.S. Patent 2,694,66X; U.S. Patent 3,15~,046; U.S. Patent 4,089,945, and U.S. Patent 4,885,107, which descriptions are incorporated herein by reference.
Pyridinethione antimicrobial agents, especially l-hydroxy-2-pyridinethione salts, are highly preferred particulate antimicrobial agents for use in the shampoo compositions~ concentrations of which range from about 0.1% to about 3%, preferably about 0.3% to about 2%, by weight of the shampoo compositions.
Preferred pyridinethione salts are those forrned from heavy metals such as zinc, tin, cadmium, magnesium, aluminum and zirconium. Zinc salts are most ~refc, - ed, especially the zinc salt of l-hydroxy-2-pyridinethione (zinc pyridinethione, ZPT).
Other cations such as sodium may also be suitable. Particularly preferred are 1-hydroxy-2-pyridinethione salts in platelet particle form, wherein the particles have an average size of up to about 20 microns, pr~felably up to about 8 microns, most preferably up to about 5 microns.
Pyridinethione antimicrobial agents are well known in the shampoo an, and are described, for example, in U.S. Patent 2,809,971, U.S Patent 3,236,733; U.S.Patent 3,753,196; U.S. Patent 3,761,418; U.S. Patent 4,345,080; U.S. Patent 4,323,683; U.S. Patent 4,379,753; and U.S. Patent 4,470,982, which des~,-iplions are incorporated herein by reference Sulfur may also be used as the particulate antimicrobial aBent in the shampoo compositions herein. Effective concenll~tions of the particulate sulfur are generally from about 1% to about 5%, more pr-,ft:~ably from about 2% to about 5%, by weight of the compositions.
Octopirox and related salts and derivatives may also be used as the antimicrobial agent in the shampoo compositions. Such antimicrobial agents are soluble in the shampoo composition and, lherefofe, do not d.spcr~e throughout the composition as crystalline par~icul~tçc as do the other antimicrobial agents described he. eh~berore.

W O 97126854 PCTrUS97/00081 Suspendin~ or Thickenin~ A~ent The shampoo compositions of the present invention comprise a suspending or thickening agent to help maintain dispersion of particulate antimicrobial agentsthroughout the composition. Any known suspending or thickening agent may be used in the shampoo compositions, provided that it is physically and chemically compatible with the essential components of the shampoo composition described herein, or does not otherwise unduly impair product stability, aesthetics or performance.
Crystalline suspending agents are preferred for suspending the par~iculate antimicrobial agent in the shampoo compositions. The selected suspending agent? at the selected concentration, should help maintain the suspension for at a period of at least one month, preferably at least three months, more preferably at least about twenty-four months, at ambient tell.pe.~tures. In general, effective concentrations of the crystalline suspending agent range from about 0.5% to about 10%, preferably from about 0.~% to about 5%, more p.efe.~bly about 1% to about 4%, most preferably about 1% to about 3%, by weight of the shampoo composition.
In general, concentrations of the crystalline suspending agent should be minimized to achieve only the desired p,ope~ Iy.
~ lefe~,ed crystalline suspending agents are acyl derivatives and amine oxides, especially acyl derivatives, especially those which can be solubilized in a premix solution and then be recryst~ 7ed upon cooling. These materials comprise long chain (e.g., Cg-C22 plef~,.ably C14-C22, more preferably C16-C22) aliphatic groups, i.e., long chain acy1 derivative materials and long chain amine oxides, as well as mixtures of such materials. In~ ded are ethylene glycol long chain esters, alkanol amides of long chain fatty acids, long chain esters of long chain fatty acids, glyceryl long chain esters, long chain esters of long chain allt~nol~nlides, and long chain alkyl ~L".~Ih~l amine oxides, and co",binations thereof.
Crystalline s~ el-cling agents are described, for example, in U.S. Patent 4,741,855, which description is incorporated herein by .efe.ence.
Suitable suspending agents for use in the shampoo compositions herein include ethylene glycol esters of fatty acids pr~f~.ably having from about 14 to about 22 carbon atoms, more preferably 16-22 carbon atoms. More prtfel-ed are the ethylene glycol stearates, both mono and distearate, but particularly the distearate containing less than about 7% of the mono stearate. Other suspending agents include alkanol amides of fatty acids, pre~erably having from about 16 to about 22 carbon atoms, more preferably about 16 to 18 carbon atoms. Preferred alkanol amides are W O 97/26854 PCT~US97100081 stearic monoethanolamid~ stearic diethanolamide, stea~ic monoisopropanolamide and stearic monoethanoiamide stearate Other long chain acyl derivatives include longchain esters of long chain fatty acids (e.g., stearyl stearate, cetyl palmitate), glyceryl esters (e g, glyceryl distearate) and long chain esters of long chain alkanol amides (e.g., stearamide diethanolamide distearate, stearamide monoethanolamide stearate) Ethylene glycol esters of long chain carboxylic acids, long chain amine oxides, and alkanol amides of long chain carboxylic acids, in addition to the preferred materials listed above, may be used as suspending agents.
Suspending agents also include long chain amine oxides such as alkyl (C16-C2~) dimethyl amine oxides, e.g., stearyl dimethyl amine oxide.
Other long chain acyl derivatives that can be used include N,N-dihydrocarbyl (C12-C22, preferably C16-CIg) amido benzoic acid and soluble salts thereof (e.g., Na and K salts), particularly N,~-di(C I 6-C 18~ and hydrogenated tallow) amido benzoic acid species of this family, which are commercially available from Stepan Company (Northfield, Illinois, USA).
The crystalline suspending agent can be incorporated into the shampoo compositions herein by solubilizing it into a solution containing water and the anionic sulfate surfactant at a temperature above the meiting point of the suspending agent.
The suspending agent is then recryst~l~i7~. typically by cooling the solution to a te"lpc.~lure sufficient to induce cryst~lli7~tion.
Other suitable suspending agents for use in the shampoo compositions include that can be used include polymeric thickeners, such as carboxyvinyl polymers, examples of which are described in U.S. Patent 2,79B,053, and U.S. Patent 4,686,254, which descriptions are incorporated herein by ~eference. Examples of suitable carboxyvinyl polymers include Carbopol(~) 934, -940, -941, -956, -980, -981, -1342, and -1382, all cor.u"e.,,;ally available from B. F. Goodrich Company Other suitable sus~end.,~g agents include those which impart a gel-like viscosity to the composition, such as water soluble or colloidally water solublepolymers like cellulose ethers (e.g., hydroxyethyl cellulose), guar gum, polyvinyl alcohol, polyvinyl pyrrolidone, hydroxypropyl guar gum, starch and starch derivatives, and other thickeners, viscosity modifiers, gelling agents, xanehan gum and combinations thereof Other suitable suspending agents are described in U.S Patent 4,788,006, which dcs.;-iption is incorporated herein by refelence CA 02242932 l998-07-l4 I ~

Cationic Guar PolYmer The shampoo compositions of the present invention comprise a cationic guar polymer having a select charge density. The cationic guar polymer~ in combination with the essential components of the compositions, provides improved deposition of the antimicrobial agent onto the scalp and other areas of the skin. Concentrations of the cationic deposition polymer range from about 0 01% to about 1.0~/0, preferably from about 0.01% to about 0.5%, more preferably from about û.02% to about 0.25%, by weight of the shampoo compositions.
The cationic guar polymer for use in the shampoo composition is fi~rther defined as having a cationic charge density of from about O.O~meq/g to about 3meq/g, preferably from about O.lmeq/g to about 2meq/g, more preferably from about 0.8 to about 1.8meq/g, wherein at least about 50%, preferably about 100%, by weight of the cationic guar polymer forms coacervates with detersive surfactant in the shampoo compositions. The formed coacervates are in the forrn of hydrated, dispersed colloids that are insoiuble in the sharnpoo compositions.
The cationic guar polymers for use in the shampoo compositions are cationically substituted galactomannan (guar) gum derivatives. The molecular weight of such derivatives ranges generally from about 2,000 to about 3,000,000. Guar gum for use in preparing these guar gum derivatives is typically obtained as a naturally occurring material from the seeds of the guar plant. The guar molecule itself is a straight chain mqnnq~ ched at regular intervals with single mcn,~e,ed galactose units on alternative mannose units. The mannose units are linked to each other by means of beta ( 1-4) glycosidic linkages. The galactose bran~hing arises by way of an alpha ( 1-6) linkage. Cationic derivatives of the guar gums are obtained by reaction between the hydroxyl groups of the polygalactomannan and reactive quaternary ammonium compounds. The degree of su~ tion of the cationic groups onto the guu structure must be suffiei~nt to provide the requisite cationic charge density des~,.il.ed k_.~,;nb~,~re.
Suitablc quaternary an,l,.onium compounds for use in forming the guar cationic polymers include R' R~ N R2 z wherein where R~, R2 and R3 are methyl or ethyl groups and R4 is an epoxyalkyl group of the formula H~C - CH-Rs-o or R4 is a halohvdrin group of the formula X--CH2-fH--R5--OH
where R5 is C l-C3 alkylene and X is chlorine or bromine, and Z is an anion such as Cl~, Br~, I- or HSO4-.
Cationic guar polymers (cationic derivatives of guar gum) formed from the reagents described hereinbefore are represented by the formula Rl R--O--CH2-CH--R5--~--R2 Z

wherein R is guar gum. Preferably, the cationic guar polymer is guar hydroxypropyltrimethylammonium chloride, which can be more specifically represented by the formula R--O--CH2-fH-CH2N~(CH~) ~CI-OH

~ specific examples of which include Jaguar(~) C- ! 3-S (cationic charge density 0.8meq/g) and Jaguar C-17 (cationic charge density 1.6meq/g) commercially available from Rhone-Poulenc Surf~ct~n~s and Specialties, Cranbury N..J. U.S.A.
Other suitable cationic guar polymers include hydroxypropylated cationic guar derivatives.

Water The shampoo compositions of the prescnt invention are nqueous systems which comprise from about 40% to about 92%, p,~feldbly from about 50% to about 85%, more preferably from about 60% to about 80%, water by weight of the composltlons.
The pH of the shampoo compositions ranges, in general, from about 2 to about 10~ preferably from about 3 to about 9, more preferably from about 4 to about X, most preferably from about 5.5 to about 7.5. For zwitterionic or amphoteric surfactant systems, the pH should be adjusted according to the isoelectric point of the selected surfactant to maintain an anionic species on the selected surfactant prior to forming a coacervate with the cationic guar polymer described herein.

W O 97126854 PCTrUS97100081 Optional ComPonents The shampoo compositions of the present invention may further comprise one or more optional components known for use in shampoo compositions, provided thatthe optional components are physically and chemically compatible with the essential components described herein, or do not otherwise unduly impair product stability, aesthetics or performance. Concentrations of such optional components typically range from about 0.00~% to about 10% by weight ofthe shampoo compositions.
Optional components include preservatives, conditioning agents, styling polymers, organic solvents, pearlescent aids, foam boosters, nonionic surfactants, pH
adjusting agents, perfumes, proteins, dyes, skin active agents, sunscreens, vitamins, and viscosity adjusting agents. This list of optional components is not meant to be exclusive, and other optional components can be used METHOD OF USE
The shampoo compositions of the present invention are used in a conventional manner for cleaning hair and controlling dandruff on the scalp. Theshampoo compositions herein are also useful for cleansing the skin and other areas of the body such as underarm and groin areas. An effective amount of the composition, typically from about I g to about 20 g of the composition, for cleaning hair, skin or other area of the body, is applied to the hair, skin or other area that has pre~lably been wetted, generally with water, and then rinsed off. Application to the hair typical!y includes working the shampoo composition through the hair such that most or all of the hair is contacted with the shampoo composition.

E~AMPLES
The compositions illustrated in Exa~,lples l-XX illustrate specific embod~ ents of the shampoo c~.l,po~ilions of the present invention, but are not intended to be limiting thereof: Other modifications can be undertaken by the skilled artisan without depa~ting from the spirit and scope of this invention. These exemplified embodiments of the shampoo compositions of the present invention provide excellent cle~n.~in~ of hair and dandruffcontrol.
All exemplified compositions can be prepaled by conventional formulation and mixing techniques. Component amounts are listed as weight percents and exclude minor materials such as diluents, filler, and so forth. The listed formulations, therefore, comprise the listed components and any minor materials associated with such components.

CA 02242932 l998-07-l4 W O 97/26854 PCT~US97100081 I _ Examples I - XVI

Component Exampl Exampl Example Example Exampl e e III IV e Il V
Arnmonium Laureth Sulfate 15.00 15 00 15 00 15 00 7 50 Ammonium Lauryl Sulfate 5 00 5 00 5 00 5 00 2 50 Sodium Lauroyl Sarcosinate 1 50 1 50 1 50 1 50 0 75 Ethylene Glycol Distearate 1.50 1.50 l 50 1 50 1 50 Zinc Pyrithione 1 00 1 00 1 00 --- 1 00 Selenium Disulfide --- - 1 00 Jaguar C17S 0 10 0 05 0 50 0 10 0 10 Fragrance q s q s q s q s q s Color q.s qs qs qs qs pH adjustment (Mono/Di sodium q.s q s q s q s q s Phosphate) viscosityadjustment (Sodium q.s q s q s q.s q s.
Chloride, preservative (D~)M Hydantoin);q.s q.s. q.s q.s q s Water Component Esample Example Example Exampl Exampl Vl V~l VIIl e e ~C X
AmmonumLaurethSulfate 750 1500 1500 10.00 1000 Ammonum Lauryl Sulfate 2.50 5 00 5 00 2 50 2 50 Co.~ idopropyl Betaine --- --- --- 2.50 2.50 Sodium Lauroyl Sarcosinate 0 75 --- --- --- ---Ethylene Glycol Distearate 1.50 1 50 1 50 1.50 1 50 zinc P~ 1.00 1.00 1.00 1.00 1.00 Ja~uar C13'' --- 0 10 JaRuarcl7~ 0.05 --- 0 10 --- 0.10 Fragrance q.s q.s q.s. q.s. q s Color qs qs qs. q.s. q.s.
pHadjustment (MonolDi sodium q.s q.s q s q.s. q s.
Phosphate) Sodium Sulfate, PEG-600, q s q s q.s q s. q s Ammonium Xylene Sulfonate) preservative (DMDM Hydantoin)q s q s q s q.s q s.
Water W O 971268~4 PCT~US97tO0081 Component Exampl Exampl Exampl Exampl Examp Exampl e e e e le e Xl XII XIII XIV XV XVI
.~nmonium Laureth Sulfate15 00 15 00 15 00 15 00 15 00 15 00 Ammonium Lauryl Sulfate 5 00 5 00 5 00 5 00 5 00 5 00 Cocamidopropyl Betaine 2 . 00 --- --- --- --- ---Sodium Lauroyl Sarcosinate --- 1 50 1 50 --- --- ---Sodium Cocoyl Glutamate --- --- --- --- 1 50 Ethylene Glycol Distearate 1 50 1 50 1 50 1 50 1 50 1 50 W O 97126854 PCT~US97/00081 Stearyl Alcohol --- --- --- --- --- --- ~
Zinc Pyrithione 1.00 0 30 0.30 0.30 0.30 1.00 Jaguar C13S 0.20 --- --- 010 0.0~ ---JaeuarC17S --- 0.10 0.05 --- --- 0.10 Fragrance ~.s. q.s. q.s q.s. q.s. q.s Color q.s. q.s. q.s. q s. q.s. q s.
pH adjustment (Mono/Di sodium q.s. q.s. q.s. 4.s. q.s. q.s Phosphate) viscosity adjustment (Sodium q s q.s. q.s. q.s. q.s. q.s Chloride,) preservative (DMDM q.s. q.s. q.s. q.s. q.s q.s.
Hydantoin) Water q.s. q.s. q.s. q.s q.s. q.s In preparing each of the compositions described in Examples I to XVI, about one-third of the ammonium laureth sulfate (added as 25wt% solution) is added to a jacketed mix tank and heated to about 74~C with slow agitation to form a surfactant solution. Salts (sodium chloride) and pH modifiers (disodium phosphate, monosodium phosphate) are added to the tank and allowed to disperse. Ethylene glycol distearate (EGDS) is added to the rnixing vessel and allowed to melt. After the EGDS is melted and dispersed (e.g., after about 5-20 minutes), preservative and additional viscosity modifier are added to the surfactant solution. The resulting mixture is passed through a heat .oYc}l~n~eerwhere it is cooled to about 3~~C and collected in a finishing tank. As a result of this cooling step, the EGDS cryst~ 7es to form a crystalline network in the product. The remainder of the ammonium laureth sulfate and other components are added to ~he finishing tank with agitation to ensure a homogeneous mixture.
Cationic gu r polymer is dispersed in water as a 0.5-2.5% ~queous solution before addition to the final mix. Once all components have bcen added, viscosityand pH modifiers are added to the mixture to adjust product viscosity and pH to the extcnt desired.
Each exe.."~lified composition provides excellent hair cle~n~ing lathering, antimicrobial agent deposition on the scalp and dandruffcontrol.

Component Example ExampleExample X VII xvm xrx Ammonium Laureth Sulfate 14.00 14 00 14.00 Cocamidopropyl Betaine --- 2.50 2 50 Cocoamphodiacetate 2.50 Cocamide MEA 1.00 I 00 I 00 Ethylene Glycol Distearate 1.50 1.50 1.50 Cetyl Alcohol 042 0.42 0.42 Stearyl Alcohol 0.18 0.18 0.18 Zinc Pyrithione 1.00 1.00 1.00 JaguarC13S 0.15 0.15 Jaguar C 1 7S --- 0 1 5 Fragrance q.s. q.s q.s.
Color q.s. q.s. q.s.
pH adjustment (Mono/Di sodium q.s. q.s. q.s.
Phosphate) viscosity adjustment (Sodium q.s. q.s. q.s.
Chloride, preservative (DMDM Hydantoin); q.s. q.s. q.s.
Water In plepc~ lg each of the compositions described in Examples XVII to XIX, from 50% to 100% by weight of the detersive surfAct~nts are added to a jacketed mix tank and heated to about 74~C with slow agitation to form a surfactant solution. If used, pH modifiers (monosodium phosphate, disodium phosphate) are added to the tank and allowed to disperse. Ethylene glycol dislealate (EGDS) and fatty alcohols (cetyl alcohol, stearyl alcohol) are then added to the n~ixing vessel and allowed to melt. After the EGDS is melted and dispe,rsed (usually about 5-10 minutes), preservative (if used) is added and mixed into the surfactant solution. Additional viscosity modifier are added to the surfactant solution if ne~esss.~r. The rçsl~lting nuxture is passed through a heat exc~l~nger where it is cooled to aboue 35~C and collected in a finishing tank. As a result of this cooling step, the EGDS cryst~lli7~s to form a crystalline network in the product. Any lc,ma;ning surfactant and other con.poncl1~s are added to the fini~hing tank with agitation to ensure a homogeneous mixture. Cationic guar polyrner is dispersed in water as a 0.5-2.5% aqueous solution before addition tothe final mix. Once all components have been added, viscosity and pH modifiers are added to the mixture to adjust product viscosity and pH to the extent desired.
Each exempiified composition provides excellent hair cle~ns;ng lathering, antimicrobial agent deposition on the scalp, and dandruffcontrol.

W 097~26854 PCT~US97/00081 Example X,Y
ComponentExample Ammonium Laureth Sulfate 15 00 Ammonium Lauryl Sulfate 5 oo Cocamide MEA 1 00 Ethylene G ycol Distearate 1.50 Zinc Pyrith one 1.00 Jaguar C13S 0.20 Color 4.s.
pH adjustment (Mono/Di sodium Phosphate) q.s.
viscosity adjustment (sodium Chloridc, q.s.
preservative (DMDM Hydantoin). Water q.s.

In preparing the composition described in Examples XX, about one-third to all of the total surfactant are added to a jacketed mix tank and heated to about 74~C with slow agitation to form a surfactant solution. Salts are added to the tank and allowed to disperse. Ethylene glycol distearate (EGDS) is then added tothe mixing vessel and allowed to melt. A~er the EGDS is melted and dispersed (usually a~er about 5-20 minutes), preservative (DMDM hydantoin) if used is added to the surfactant solution. The res..hing mixture is passed through a heatexchanger where it is cooled to about 35~C and collected in a finishing tank. As a result of this cooling step, the EGDS cryst~lli7es to form a crystalline network in the product. The remainder of the detersive surfactant and other components are added to the finishing tank with agitation to ensure a homogeneous mixture.
Cationic guar polymer is dispersed in water as a 0.5-2.5% aqueous solution before ~ditiQn to the final mix. Once ail components have been added, viscosity and pH modifiers are added to the mixture to adjust product viscosity and pH to the extent desired.
The resulting composition provides excellent hair cleansing, lathering, antimicrobial agent deposition on the scalp and dandruff control.

Claims (8)

WHAT IS CLAIMED IS:

1. A shampoo composition with improved deposition of antimicrobial agents, said composition comprising:
(a) from 7% to 30% by weight of a detersive surfactant selected from the group consisting of anionic surfactants, amphoteric surfactants, zwitterionic surfactants, and combinations thereof, preferably anionic surfactant, (b) from 0. 1% to 10% by weight of an antimicrobial agent, (c) from 0. 5% to 10% by weight of a suspending agent;
(d) from 0.01% to 1.0% by weight of a cationic guar polymer having a charge density of from 0.01meq/g to 3meq/gm; and (e) from 40% to 92% by weight of water;
wherein at least 50% by weight of the cationic guar polymer is in coacervate form, said coacervate comprising detersive surfactant and cationic guar polymer.

2. The shampoo composition of Claim 1 wherein the antimicrobial agent is a crystalline, particulate material selected from the group consisting of sulfur, selenium sulfide, pyridinethione salts, and combinations thereof, preferably the zinc salt of 1-hydroxy-2-pyridinethione.

3. The shampoo composition of any one of the preceding claims wherein the composition is substantially free of N-acyl amino acid surfactants.

4. The shampoo composition of any one of the preceding claims wherein the cationic guar polymer has a cationic charge density of from 0.1meq/g to 2meq/g.

5 The shampoo composition of any one of the preceding claims wherein the concentration of the anionic detersive surfactant is from 12% to 22% by weight of the composition.

6. The shampoo composition any one of the preceding claims wherein the detersive surfactant comprises an N-acyl amino acid surfactant, and the cationic guar polymer has a cationic charge density of from 0.9meq/g to 3meq/g.

7 A shampoo composition with improved deposition of particulate antimicrobial agents, said composition comprising:
(a) from 10% to 25% by weight of an anionic detersive surfactant;
(b ) from 0.1 % to 10% by weight of a crystalline, particulate antimicrobial agent selected from the group consisting of sulfur, selenium sulfide, pyridinethione salts, and combinations thereof, preferably the zinc salt of 1-hydroxy-2-pyridinethione;
(c) from 0.5% to 10% by weight of a crystalline suspending agent;
(d) from 0.01% to 0.5% by weight of a cationic guar polymer having a charge density of from 0.1 meq/g to 2meq/gm; and (e) from 50% to 85% by weight of water;
wherein at least 50% by weight of the cationic guar polymer is in coacervate form, said coacervate comprising detersive surfactant and cationic guar polymer, and wherein the composition is substantially free of N-acyl amino acid surfactants.

8. The shampoo composition of any one of the preceding claims wherein the cationic guar polymer is guar hydroxypropyltrimethylammonium chloride.