WO2016024090A1

WO2016024090A1 - Bar soap composition

Info

Publication number: WO2016024090A1
Application number: PCT/GB2015/052250
Authority: WO
Inventors: Richard John Kosturko; Emeka OKAFOR; Candice Lida Taylor; Haoming Yuan
Original assignee: Reckitt Benckiser Llc; Reckitt Benckiser (Brands) Limited
Priority date: 2014-08-13
Filing date: 2015-08-04
Publication date: 2016-02-18
Also published as: GB201414344D0

Abstract

A semi-translucent bar soap composition provides an effective antimicrobial benefit against gram positive and gram negative bacteria, which bar soap compositions comprises: a) u p to 1%wt. of an antimicrobial system which comprises lemon grass oil. b) at least 55% of salts of C₁₂, C₁₄,C₁₆ and C₁₈ saturated fatty acids. c) a non-quaternary ammonium based germicidal compound.

Description

BAR SOAP COMPOSITION The present invention relates to bar soap compositions which are particularly usefu l in personal care applications, e.g. topical skin care, cleansing, which bar soap compositions exhibit an appreciable antimicrobial benefit.

Bar soaps are amongst the oldest forms of personal cleansing prod ucts. They are relatively easy to produce as they are the form of solid bars or cakes, req uire the simplest of packaging, typica lly boast long shelf storage lives, and of cou rse a re effective in providing a cleaning benefit. Many variations of such bar soa ps are also known, and also widely available are bar soa ps which additiona lly boast an antimicrobial benefit. These are generally provided by the addition of known antimicrobial constituents, such as those based on antimicrobial free metal ions (e.g. Ag⁺, Cu²⁺, Zn²⁺), phenolic antimicrobial compou nds (e.g. TRICLOSAN®, PCMX, TCC), and non-phenolic antimicrobial compou nds (e.g. certain quaternary ammoniu m salts) which independently of the bar soap composition provide an antimicrobial benefit. The addition of these antimicrobial constituents, although well known to be effective, a re also facing increasing scrutiny from regu latory agencies, and additionally req uire added material handling and costs d uring the prod uction process of bar soa ps containing such constituents.

According to a first aspect of the present invention there is provided a semi- translucent bar soap composition which provides an effective antimicrobial benefit against gram positive and gram negative bacteria, which bar soap compositions comprises:

a) u p to l%wt. of an antimicrobial system which comprises lemon grass oil.

b) at least 55% of salts of Ci₂, C_i4 ,C₁₆ and Ci₈ saturated fatty acids.

c) a non-quaternary ammoniu m based germicidal compou nd .

The composition is preferably used in a cosmetic cleaning operation . Thus according to a second aspect of the present invention there is provided a method for providing a germicidal benefit to a topical surface, especially a dermal surface, the method comprising the step of: contacting a topical surface upon which the presence of one or more undesired pathogens, preferably bacteria, are known or suspected, with a bar soap composition according to a first aspect of the invention.

It is to be expressly understood that as used herein, "bar soap composition" refers to a composition which may, subject to appropriate processing conditions (e.g. compression) be formed into a generally rigid, self-supporting solid bar soap, and references regarding the identity of constituents and weight percentages of a bar soap composition are similarly applicable to bar soaps formed therefrom.

The composition / method of the present invention provide as a primary technical benefit the reduction of undesired microorganisms, particularly in the reduction of both gram positive and gram negative microorganisms, while at the same time providing secondary benefits including skin conditioning and/or skin cleansing. Further ancillary benefits may be provided by the presence of one or more optional constituents which may be included in formulations or compositions according to the present intervention.

In more detail it has been observed that the bar soap composition is characterized in exhibiting at least a 3 log 10 reduction of Klebsiella pneumoniae when tested according to the standardized test protocols of ASTM E I 053 Standard Test Method to Assess Virucidal Activity of Chemicals Intended for Disinfection of Inanimate, Nonporous Environmental Surfaces.

These aspects and advantages of the invention are discussed in more detail hereinafter, particularly in reference to one or more of the examples set forth below. Preferably the translucency is such that <100% of light transmitted through the soap bar is absorbed. More preferably less than 95% of transmitted light and most preferably less than 90% of transmitted light is absorbed. Such absorbance may be measured using, for example, a Hunter Colorimter Labscan XE.

Lemonarass

Lemon grass (Cymbopogon citratus) belongs to the family Poaceae. It is a tall perennial grass with slender sharp edge green leaves that have a pointed apex. It is native to warm temper- ate and tropical regions.

In order to extract the oil from the plant, typically the plant is washed and then air dried for two weeks. The leaves are then ground to a particle size of around 0.5mm. Usually the active oil is extracted with a solvent such as ethanol or a chlorinated solvent such as dichloro- methane. The solvent can be removed using, for example, a rotary evaporator, to yield the oil.

Without wishing to be bound by theory it is understood that one of the main constituents of the many different species of lemongrass is citral (3,7-dimethyl-2,6-octadien-l-al) (Abe, S., Sato, Y., Inoue, S., Ishibashi, H., Maruyama, N., Takizawa, T., Oshima, H., and Yamaguchi, H). Nippon Ishinkin Gakkai Zasshi 2003;44(4):285-291. 14615795).

Lemongrass oil has been found to contain up to 75-85% citral. Lemongrass also contains z- citral, borneol, estragole, methyleugenol, geranyl acetate (3,7-dimethyl-2,6-octadiene-l-ol acetate), geraniol (some species higher in this compound than citral), beta-myrcene (MYR, 7- methyl-3-methylene-l,6 octadiene), limonene, piperitone, citronellal, carene-2, alpha- terpineole, pinene, farnesol, proximadiol, and (+)-cymbodiacetal. The volatile oil from the roots contains 56.67% longifolene-(V4) and 20.03% selina-6-en-4-ol. In particular, a study of Cymbopogon martinii isolated fatty acids, common sterols, and 16-hydroxypentacos-14(z)- enoic acid.

Citral, or 3,7-dimethyl-2,6-octadienal or lemonal, is either a pair, or a mixture of terpenoids with the molecular formula CioHi_S0. The two compounds are double bond isomers. The E- isomer is known as geranial or citral A. The Z-isomer is known as neral or citral B.

Citral- a(Cvanial CftraJrbpTaral) ftm f urm) [as form) Soaps used in the soap constituent of the present invention are known to the art as saponified fatty acids, having typically having from about 8 to about 24 carbon atoms, preferably from about 10 to about 20 carbon atoms, which are supplied from a variety of fatty acid sources. Such sources include natural sources such as, for instance, plant or animal-derived glycerides (e.g. palm oil, coconut oil, soybean oil, castor oil, tallow, lard, etc.). The fatty acids can also be synthetically prepared. Soaps may be prepared by either direct saponification of fats and oils or by neutralization of free fatty acids. Particularly useful are the sodium, ammonium and alkanolammonium salts of lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, ricinoleic acid, coconut fatty acid, palm kernel fatty acid and tallow fatty acid, as well as technical grade mixtures thereof. Of these, sodium salts of saponified naturally occurring fatty acids are overwhelmingly predominant in the industry as such sources of fatty acids are relatively cheap, and sodium is both effective, widely available and effectively aids in the aq ueous dissolution of the saponified fatty acids. However, with the sourcing of fatty acids from natu ral sources the distribution of the specific acids within such a composition may vary widely and typica lly a tech nical grade mixtu re is provided which may vary from batch to batch, and which does not necessarily consistently incl ude specific ratios or distributions of specific fatty acids within such a tech nical grade mixtu re.

The soap constituent comprises at least 55% but preferably, is at least (in order of increasing preference, in %) 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94.5, 95, 95.5, 96, 96.5, 97, 97.5, 98, 98.5, 99, and 99.5% of salts of C₁₂, C_M, Ci₆and Ci₈ saturated fatty acids.

The bar soap compositions of the invention may additiona lly include one or more anionic, nonionic, amphoteric or zwitterionic su rfactants, particularly where such a re provided to increase the prod uction of foam or lather when the bar soap is used in a manual cleaning op- eration, e.g. washing of the hands, body or hair. Such surfactants are distinguished from the soap constituent described herein . Such a re freq uently referred to as synthetic surfactants, or "syndets" as they are distinguished from the fatty acid based soa ps (frequently su pplied as "soap noodles") which is the major constituent of the present invention . By way of non- limiting example, such include anionic su rfactants which may be used in this capacity in the bar soaps include one or more of: alcohol sulfates and su lfonates, alcohol phosphates and phosphonates, alkyl ester sulfates, al kyl diphenyl ether su lfonates, alkyl su lfates, alkyl ether su lfates, su lfate esters of an alkylphenoxy polyoxyethylene ethanol, alkyl monoglyceride sulfates, alkyl su lfonates, alkyl ether su lfates, al pha-olefin sulfonates, beta-alkoxy al kane sulfonates, alkyl ether su lfonates, ethoxylated al kyl su lfonates, alkylaryl sulfonates, alkylaryl sul- fates, alkyl monoglyceride sulfonates, al kyl carboxylates, alkyl ether carboxylates, alkyl alkoxy carboxylates having 1 to 5 moles of ethylene oxide, alkylpolyglycolethersulfates (containing u p to 10 moles of ethylene oxide), su lfosuccinates, octoxynol or nonoxynol phosphates, ta urates, fatty ta urides, fatty acid amide polyoxyethylene sulfates, acyl glycerol sulfonates, fatty oleyl glycerol sulfates, al kyl phenol ethylene oxide ether su lfates, paraffin sul- fonates, alkyl phosphates, isethionates, N-acyl taurates, alkyl succinamates and sulfosuccin- ates, alkylpolysaccharide sulfates, alkylpolyglucoside sulfates, alkyl polyethoxy carboxylates, and sarcosinates or mixtures thereof. Further examples of anionic surfactants include water soluble salts or acids of the formula (ROS0₃)_xM or (RS0₃)_xM wherein R is preferably a C₃-C₂₄ hydrocarbyl, preferably an alkyl or hydroxyalkyl having a Ci₀-C₂₀ alkyl component, more preferably a Ci₂-Ci₈ alkyl or hydroxy- alkyl, and M is H or a mono-, di- or tri-valent cation, e.g. an alkali metal cation (e.g. sodium, potassium, lithium), or ammonium or substituted ammonium (e.g. methyl-, dimethyl-, and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethyl- ammonium and dimethyl piperdinium cations and quaternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like) and x is an integer, preferably 1 to 3, most preferably 1. Further examples of anionic surfactants include alkyl-diphenyl-ethersulphonates and alkyl- carboxylates. Other anionic surfactants are C₃-C₂₀ linear alkylbenzenesulfonates, C₃-C₂₂ primary or secondary alkanesulfonates, C₃-C₂₄ olefinsulfonates, sulfonated polycarboxylic acids prepared by sulfonation of the pyrolyzed product of alkaline earth metal citrates, C₃-C₂₄ al- kylpolyglycolethersulfates , alkyl ester sulfates such as Ci₄_i_S methyl ester sulfates; acyl glyc- erol sulfonates, fatty oleyl glycerol sulfates, alkyl phenol ethylene oxide ether sulfates, paraffin sulfonates, alkyl phosphates, isethionates such as the acyl isethionates, N-acyl taurates, alkyl succinamates and sulfosuccinates, monoesters of sulfosuccinate (especially saturated and unsaturated Ci₂-Ci₈ monoesters) diesters of sulfosuccinate (especially saturated and unsaturated C₃-Ci4 diesters), acyl sarcosinates, sulfates of alkylpolysaccharides such as the sul- fates of alkylpolyglucoside (the nonionic nonsulfated compounds being described below), branched primary alkyl sulfates, alkyl polyethoxy carboxylates such as those of the formula RO(CH₂CH₂0)_kCH₂COO^"M⁺ wherein R is a C₈-C₂₂ alkyl, k is an integer from 0 to 10, and M is a soluble salt-forming cation. When present, such one or more anionic surfactants may be present in any effective amount, and advantageously comprise up to about 20%wt. of the bar soap compositions of which they form a part. Non-limiting examples of nonionic surfactants which may be used in the bar soaps include one or more of: alkyl glucosides, alkyl polyglucosides, polyhydroxy fatty acid amides, alkox- ylated fatty acid esters, amine oxides, and mixtures thereof. Further nonionic surfactants include almost any hydrophobic compound having a carboxy, hydroxy, amido, or amino group with a free hydrogen attached to the nitrogen which can be condensed with alkylene oxide (e.g. ethylene oxide, propylene oxide) or with the polyhydration product thereof, polyethylene glycol, to form a water soluble nonionic surfactant compound. Further, the length of the polyethenoxy hydrophobic and hydrophilic elements may various. Exemplary nonionic compounds include the polyoxyethylene ethers of alkyl aromatic hydroxy compounds, e.g. alkylated polyoxyethylene phenols, polyoxyethylene ethers of long chain aliphatic alcohols, the polyoxyethylene ethers of hydrophobic propylene oxide polymers, and the higher alkyl amine oxides.

Examples of nonionic surfactants include primary and secondary linear and branched alcohol ethoxylates, such as those based on C₃-Ci₈ alcohols which further include an average of from 2 to 80 moles of ethoxylation per mol of alcohol. Examples include the Genapol^® series of linear alcohol ethoxylates from Clariant Corp., Charlotte, NC. Further nonionic surfactants include secondary Ci₂-Ci₅ alcohol ethoxylates, including those which have from about 3 to about 10 moles of ethoxylation. Such are available in the Tergitol^® series of nonionic surfactants (Dow Chemical, Midland, Ml), particularly those in the Tergitol^® "15-S-"series. Still fur- ther examples of suitable nonionic surfactants for use as the (b) at least one nonionic surfactant include which may be advantageously included in the inventive compositions are alkoxy block copolymers, and in particular, compounds based on ethoxy/propoxy block copolymers. Polymeric alkylene oxide block copolymers include nonionic surfactants in which the major portion of the molecule is made up of block polymeric C₂-C alkylene oxides. Such nonionic surfactants, while preferably built up from an alkylene oxide chain starting group, and can have as a starting nucleus almost any active hydrogen containing group including, without limitation, amides, phenols, thiols and secondary alcohols. Such are available in the Pluron- ic^® series of block copolymer surfactants (ex. BASF).

Examples of alkylpolyglycoside compounds include those which include alkyl monoglycosides and polyglycosides which may be prepared generally by reacting a monosaccharide, or a compound hydrolyzable to a monosaccharide with an alcohol such as a fatty alcohol in an acid medium. Exemplary alkyl glycoside surfactants alkyl glycoside surfactants suitable for use in the bar soaps of the present invention may be represented by formula (II) below:

wherein:

R is a monovalent organic radical containing from about 6 to about 30, preferably from about 8 to about 18 carbon atoms;

Ri is a divalent hydrocarbon radical containing from about 2 to about 4 carbon atoms;

O is an oxygen atom;

y is a number which has an average value from about 0 to about 1 and is preferably 0;

G is a moiety derived from a reducing saccharide containing 5 or 6 carbon atoms; and

x is a number having an average value from about 1 to 5 (preferably from 1.1 to 2);

Z is OzM¹,

O II

— 0-C-R₂ 0(CH₂), COzM¹, OSOaM¹, or OiCh^SOaM¹; R₂ is (CH^COzM¹ or CH^CHCOzM¹;

(with the proviso that Z can be O2M¹ only if Z is in place of a primary hydroxyl group in which the primary hydroxyl-bearing carbon atom,

— CH₂OH, is oxidized to form a

0

II

C— 0M1

group);

b is a number of from 0 to 3x+l preferably an average of from 0.5 to 2 per gly- cosal group;

p is 1 to 10,

M¹ is H⁺ or an organic or inorganic cation, such as, for example, an alkali metal, ammonium, monoethanolamine, or calcium.

As defined in Formula II above, R is generally the residue of a fatty alcohol having from about 8 to 30 and preferably 8 to 18 carbon atoms. Examples of such alkylglycosides as described above include, for example, APG^® 225 which is described as being an alkyl polyglycoside in which the alkyl group contains 8 to 10 carbon atoms and having an average degree of polymerization of 1.7, APG^® 325 CS GLYCOSIDE which is described as being a 50% C₉-Cn alkyl polyglycoside, also commonly referred to as D-glucopyranoside, Glucopon^® 425, described to be an alkyl polyglycoside in which the alkyl group contains 8 to 16 carbon atoms and having an average degree of polymerization of 1.48, Glucopon^® 625 CS which is described as being a 50% C10-C16 alkyl polyglycoside, also commonly referred to as a D-glucopyranoside, (available from Cognis Corp., Ambler PA), Plantaren^® 2000, described as being an alkyl polyglycoside in which the alkyl group contains 8 to 16 carbon atoms and having an average degree of polymerization of 1.4, and Plantaren^® 1300, described to be an alkyl polyglycoside in which the alkyl group contains 12 to 16 carbon atoms and having an average degree of polymerization of 1.6. Further, and sometimes preferred nonionic surfactants which may be used in the bar soaps of the invention include certain alkanolamides including monoethanolamides and diethano- lamides, particularly fatty monoalkanolamides and fatty dialkanolamides. Commercially available monoethanol amides and diethanol amides include those marketed under the trade names Alakamide^® and Cyclomide^® by Rhone-Poulenc Co., (Cranbury, NJ).

The bar soap compositions of the invention may include one or more sucrose ester based nonionic surfactants. Such are compounds which consist largely of sucrose mono- and di- esters of the natural fatty acids having 12 to 20 carbon atoms and preferably those having 16 to 20 carbon atoms. By way of non-limiting example, such include sucrose cocoate, sucrose dilaurate, sucrose distearate, sucrose laurate, sucrose myristate, sucrose oleate, sucrose palmitate, sucrose polylaurate, sucrose polylinoleate, sucrose polyoleate, sucrose polystea- rate, sucrose stearate, sucrose tetrastearate, sucrose tribehenate, sucrose tristearate or any combination thereof. Of these, preferred are sucrose cocoate and sucrose laurate, of which sucrose cocoate is particularly preferred. Whereas a mixture of sucrose ester based nonionic surfactants may be used, in certain particularly preferred embodiments it is preferred that the predominant sucrose ester based nonionic surfactant present is sucrose cocoate. In certain preferred embodiments, sucrose cocoate comprises at least 60%wt, and in order of increasing preference at least 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99% and 100% by weight of the sucrose ether based nonionic surfactant constituent. When present the one or more sucrose ester based nonionic surfactants comprise from 0.001%wt. to about 3%wt., but more preferably from 0.05%wt. to about l%wt. of bar soap compositions.

Exemplary useful amphoteric and zwitterionic surfactants include one or more of: alkyl beta- ines, alkyl amidobetaines, aminopropionates, aminoglycinates, imidazolinium betaines and sulfobetaines. Alkyl betaines are known surfactants which are mainly produced by carboxy- alkylation, preferably carboxymethylation of aminic compounds. Typical examples are the carboxymethylation products of hexyl methyl amine, hexyl dimethyl amine, octyl dimethyl amine, decyl dimethyl amine, dodecyl methyl amine, dodecyl dimethyl amine, dodecyl ethyl methyl amine, C12/14 cocoalkyl dimethyl amine, myristyl dimethyl amine, cetyl dimethyl amine, stearyl dimethyl amine, stearyl ethyl methyl amine, oleyl dimethyl amine, Ci_S/i₈ tallow alkyl dimethyl amine and technical mixtures thereof. Alkyl amidobetaines which represent carboxyalkylation products of amidoamines are also suitable. Typical examples are re- action products of fatty acids containing 6 to 22 carbon atoms, namely caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, isos- tearic acid, oleic acid, elaidic acid, petroselic acid, linoleic acid, linolenic acid, elaeostearic acid, arachic acid, gadoleic acid, behenic acid and erucic acid and technical mixtures thereof, with Ν,Ν-dimethylaminoethyl amine, Ν,Ν-dimethylaminoproply amine, N,N- diethylaminoethyl amine and Ν,Ν-diethylaminoproply amine which are condensed with sodium chloroacetate.

When present, one or more of such anionic, nonionic, amphoteric or zwitterionic surfactants may be included in any effective amount. When present, such one or more said surfactants comprise about 0.1 - 25%wt. of the bar soap of which they form a part.

The bar soap compositions may additionally include a non-quaternary ammonium based germicidal compound. Non-limiting examples of these compounds include: benzoyl peroxide, pyrithiones (especially zinc pyrithione which is also known as ZPT), dimethyldimethylol hydantoin (Glydant), methylchloroisothiazolinone/methylisothiazolinone (Kathon CG), sodium sulfite, sodium bisulfite, imidazolidinyl urea (Germall 115), diazolidinyl urea (Germaill II), benzyl alcohol, 2-bromo-2-nitropropane-l,3-diol (Bronopol), formalin (formaldehyde), io- dopropenyl butylcarbamate (Polyphase P100), chloroacetamide, methanamine, methyldi- bromonitrile glutaronitrile (l,2-Dibromo-2,4-dicyanobutane or Tektamer), glutaraldehyde, 5- bromo-5-nitro- 1,3-dioxane (Bronidox), phenethyl alcohol, o-phenylphenol/sodium o- phenylphenol, sodium hydroxymethylglycinate (Suttocide A), polymethoxy bicyclic oxazoli- dine (Nuosept C), dimethoxane, thimersal dichlorobenzyl alcohol, captan, chlorphenenesin, dichlorophene, chlorbutanol, glyceryl laurate, halogenated diphenyl ethers like 2,4,4- trichloro-2-hydroxy-diphenyl ether (Triclosan or TCS), 2,2-dihydroxy-5,5-dibromo-diphenyl ether, phenolic compounds like phenol, 2-methyl phenol, 3-methyl phenol, 4-methyl phenol, 4-ethyl phenol, 2,4-dimethyl phenol, 2,5-dimethyl phenol, 3,4-dimethyl phenol, 2,6-dimethyl phenol, 4-n-propyl phenol, 4-n-butyl phenol, 4-n-amyl phenol, 4-tert-amyl phenol, 4-n-hexyl phenol, 4-n-heptyl phenol, mono- and poly-alkyl and aromatic halophenols such as p- chlorophenol, methyl p-chlorophenol, ethyl p-chlorophenol, n-propyl p-chlorophenol, n- butyl p-chlorophenol, n-amyl p-chlorophenol, sec-amyl p-chlorophenol, n-hexyl p- chlorophenol, cyclohexyl p-chlorophenol, n-heptyl p-chlorophenol, n-octyl p-chlorophenol, o-chlorophenol, methyl o-chlorophenol, ethyl o-chlorophenol, n-propyl o-chlorophenol, n- butyl o-chlorophenol, n-amyl o-chlorophenol, tert-amyl o-chlorophenol, n-hexyl o- chlorophenol, n-heptyl o-chlorophenol, o-benzyl p-chlorophenol, o-benzyl-m-methyl p- chlorophenol, o-benzyl-m, m-dimethyl p-chlorophenol, o-phenylethyl p-chlorophenol, o- phenylethyl-m-methyl p-chlorophenol, 3-methyl p-chlorophenol, 3,5-dimethyl p- chlorophenol, 6-ethyl-3-methyl p-chlorophenol, 6-n-propyl-3-methyl p-chlorophenol, 6-iso- propyl-3-methyl p-chlorophenol, 2-ethyl-3,5-dimethyl p-chlorophenol, 6-sec-butyl-3-methyl p-chlorophenol, 2-iso-propyl-3,5-dimethyl p-chlorophenol, 6-diethylmethyl-3-methyl p- chlorophenol, 6-iso-propyl-2-ethyl-3-methyl p-chlorophenol, 2-sec-amyl-3,5-dimethyl p- chlorophenol 2-diethylmethyl-3,5-dimethyl p-chlorophenol, 6-sec-octyl-3-methyl p- chlorophenol, p-chloro-m-cresol, p-bromophenol, methyl p-bromophenol, ethyl p- bromophenol, n-propyl p-bromophenol, n-butyl p-bromophenol, n-amyl p-bromophenol, sec-amyl p-bromophenol, n-hexyl p-bromophenol, cyclohexyl p-bromophenol, o- bromophenol, tert-amyl o-bromophenol, n-hexyl o-bromophenol, n-propyl-m,m-dimethyl o- bromophenol, 2-phenyl phenol, 4-chloro-2-methyl phenol, 4-chloro-3-methyl phenol, 4- chloro-3,5-dimethyl phenol, 2,4-dichloro-3,5-dimethylphenol, 3,4,5,6-terabromo-2- methylphenol, 5-methyl-2-pentylphenol, 4-isopropyl-3-methylphenol, para-chloro-meta- xylenol ("PCMX"), dichloro meta xylenol, chlorothymol, 5-chloro-2-hydroxydiphenylmethane, resorcinol and its derivatives including methyl resorcinol, ethyl resorcinol, n-propyl resor- cinol, n-butyl resorcinol, n-amyl resorcinol, n-hexyl resorcinol, n-heptyl resorcinol, n-octyl resorcinol, n-nonyl resorcinol, phenyl resorcinol, benzyl resorcinol, phenylethyl resorcinol, phenylpropyl resorcinol, p-chlorobenzyl resorcinol, 5-chloro 2,4-dihydroxydiphenyl methane, 4-chloro 2,4-dihydroxydiphenyl methane, 5-bromo 2,4-dihydroxydiphenyl methane, and ^ bromo 2,4-dihydroxydiphenyl methane, bisphenolic compounds like 2,2-methylene bis (4 chlorophenol), 2,2-methylene bis (3,4,6-trichlorophenol), 2,2-methylene bis (4-chloro-6- bromophenol), bis (2-hydroxy-3,5-dichlorophenyl) sulphide, and bis (2-hydroxy-5- chlorobenzyl)sulphide, benzoic esters (parabens) like methylparaben, propylparaben, bu- tylparaben, ethylparaben, isopropylparaben, isobutylparaben, benzylparaben, sodium methylparaben, and sodium propylparaben, halogenated carbanilides (e.g., 3,4,4- trichlorocarbanilides (Triclocarban or TCC), 3-trifluoromethyl-4,4-dichlorocarbanilide, 3,3, trichlorocarbanilide, etc.).

Of these, preferred are phenol based non-cationic microbicidals (antimicrobial constituents), especially those based on one or more phenolic compounds, particularly 2-hydroxydiphenyl compounds which may be exem lified by the following classes of compounds:

wherein Y is chlorine or bromine, Z is S0₂ H, N0₂, or Ci -C₄ alkyl, r is 0 to 3, o is 0 to 3, p is 0 or 1, m is 0 or 1, and n is 0 or 1. In preferred embodiments, Y is chlorine or bromine, m is 0, n is 0 or 1, o is 1 or 2, r is 1 or 2, and p is 0, and according to especially preferred embodiments, Y is chlorine, m is 0, n is 0, o is 1, r is 2, and p is 0. Particularly useful 2-hydroxydiphenyl compounds include those which may be represented by the structure:

which is commonly referred to as "TRICLOSAN" and which is presently commercially ava ble from Ciba Specialty Chemicals Corp., as well as halogenated carbanilides, e.g., TCC.

Further exemplary useful phenolic based antimicrobial constituents agents include 2,2'- hydroxy-5,5'-dibromo-diphenyl ether which may be represented by the structure:

wherein Ri is hydro, hydroxy, Ci -C₄ alkyl, chloro, nitro, phenyl, or benzyl; R₂ is hydro, hydroxy, Ci -C₃ alkyl, or halo; R₃ is hydro, Ci -C₃ alkyl, hydroxy, chloro, nitro, or a sulfur in the form of an alkali metal salt or ammonium salt; R₄ is hydro or methyl, and R₅ is hydro or nitro. Halo is bromo or, preferably, is chloro.

Specific examples of phenol derivatives include, but are not limited to, chlorophenols (o-, m-, p-), 2,4-dichlorophenol, p-nitrophenol, picric acid, xylenol, p-chloro-m-xylenol, cresols (o-, m- , p-), p-chloro-m-cresol, pyrocatechol, resorcinol, 4-n-hexylresorcinol, pyrogallol, phloroglu- cin, carvacrol, thymol, p-chlorothymol, o-phenylphenol, o-benzylphenol, p-chloro-o- benzylphenol, phenol, 4-ethylphenol, and 4-phenolsulfonic acid.

Still further useful phenol derivatives include those which may be represented by the struc- ture:

wherein X is sulfur or a methylene group, Ri and R'i are hydroxy, and R₂, R'2, R3, R' 3, R₄, R'₄, R5, and R'₅, independent of one another, are hydro or halo. Specific, nonlimiting examples of diphenyl compounds are hexachlorophene, tetrachlorophene, dichlorophene, 2,3- dihydroxy-5,5'-dichlorodiphenyl sulfide, 2,2'-dihydroxy-3,3',5,5'-tetrachlorodiphenyl sulfide, 2,2'-dihydroxy-3,5',5,5', 6,6'-hexachlorodiphenyl sulfide, and 3,3'-dibromo-5,5'-dichloro-2,2'- dihydroxydiphenylamine. Of the foregoing, a particularly useful phenol derivative is commonly referred to as triclocarban, or 3,4,4'-trichlorocarbanilide as well as derivatives thereto.

More preferably said non-quaternary ammonium based germicidal compound is TCC and/or PCMX.

When present in a bar soap composition, the least one non-quaternary ammonium based germicidal compound may be present in any effective amount, but generally need not be present in amounts in excess of about 10%wt. based on the total weight of the animate sur- face treatment composition of which it forms a part. Preferably, when present, the non- quaternary ammonium based germicidal compound(s) may be present in the inventive compositions in amounts of from about 0.001 %wt. to up to about 10%wt., very preferably about 0.01-8%wt., more preferably in amounts of between about 0.01-2%wt., and most preferably from about 0.01 - l%wt. It is particularly advantageous that the preferred non- quaternary ammonium based germicidal compound(s) are present in amounts of at least about 200 parts per million (ppm), preferably in amounts of from about 1 ppm to 10,000 ppm, preferably from about 50 ppm to 2000 ppm, more preferably in amounts of from about 100 ppm to 1,000 ppm. The bar soaps of the present invention may include still further constituents. Non-limiting examples of such further constituents are described herein.

The bar soap compositions may include an effective amount of an anti-acne agent. Such may be any compound, composition or material which has been approved by the U.S. Food and Drug Ad ministration for the topical treatment of acne. Examples of anti-acne agents include, but a re not limited to, salicylic acid, benzoyl peroxide, sulph ur, retinoic acid, Ca ndida bom- bicola/glucose/methyl rapeseedate ferment, peat water, resorcinol, silt, peat, permethin, azelaic acid, clindamycin, adapalene, erythromycin, sodiu m su lfacetamide, and combinations thereof. Of these, benzoyl peroxide is particularly preferred .

Fu rther usefu l constituents include one or more al kyl lactates, which may of themselves provide an antimicrobial benefit. Such include the reaction prod ucts of a C₈-Ci₈ fatty alcohol with lactic acid . Preferred alkyl lactates include those represented by the fol lowing general structu ral formu la (la):

in which R is a C₈-Ci₈ alkyl moiety, preferably is a Ci₀-Ci₄ al kyl moiety and especially preferably is predominantly (at least 85%, more preferably at least 90%, particularly prefera bly at least 95% and most preferably at least about 98%) of a C₁₂ al kyl moiety. The al kyl moiety may be branched but is preferably su bsta ntia lly linear. A particularly preferred alkyl lactate conforming to formu la (la) is lau ryl lactyl lactate. Preferred alkyl lactates also include those represented by the fol lowing general structu ral formu la (l b):

in which R is a C₈-Ci₈ alkyl moiety, preferably is a Ci₀-Ci al kyl moiety and especially preferably is predominantly (at least 85%, more preferably at least 90%, particularly prefera bly at least 95% and most preferably at least about 98%) of a C₁₂ al kyl moiety. The al kyl moiety may be branched but is preferably su bsta ntia lly linear. A particularly preferred alkyl lactate conforming to formula (lb) is lauryl lactyl lactate. Of course it is to be understood that other alkyl lactates not specifically encompassed by the compounds of formula (la) and/or (lb) may also be utilized. When present such one or more alkyl lactates may be present in any effective amount, but advantageously comprise between about 0.001%wt. to about 3%wt., more preferably between about 0.05%wt. to about 0.5%wt. of a bar soap composition.

The soap bars may include one or more polyols. Such include compounds having two or more hydroxyl groups and which are highly water soluble, preferably freely soluble, in water. Non-limiting examples of suitable polyols include: relatively low molecular weight short chain polyhydroxy compounds such as glycerol and propylene glycol; sugars such as sorbitol, mani- tol, sucrose and glucose; modified carbohydrates such as hydrolyzed starch, dextrin and maltodextrin, and polymeric synthetic polyols such as polyalkylene glycols, for example poly- oxyethylene glycol (PEG) and polyoxypropylene glycol (PPG). Of these said polyols, preferred are relatively low molecular weight compound which are either liquid or readily soluble in aqueous solutions, e.g., low molecular weight polyols and sugars. Particularly preferred polyols are glycerine, glycerol, sorbitol and their mixtures. Glycerine and glycerol are particularly preferred, as such may also provide benefits as hu- mectants in the bar soaps.

When present, such one or more polyols may be included in minor but effective amounts, e.g., from about 0.001%wt. to about 0.5%wt., more preferably from about 0.1 -10%wt. and especially preferably from about 0.5 - 9%wt. based on the total weight of the bar soap of which it forms a part.

The bar soap compositions of the invention may include one or more stearyl alkanoates, preferably one or more selected from stearyl caprylate, stearyl palmitate, stearyl stearate, stearyl behenate, and stearyl olivate. Of these, stearyl heptanoate is particularly preferred. Whereas a mixture of stearyl alkanoates may be used, in certain particularly preferred em- bodiments it is preferred that the predominant stearyl alkanoate present is stearyl heptanoate. In certain preferred embodiments, stearyl heptanoate comprises at least 60%wt, and in order of increasing preference at least 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99% and 100% by weight of the stearyl alkanoates present. The overall content of the one or more stearyl alkanoates in the bar soap compositions is preferably from 0.001%wt. to about 5%wt., more preferably is from 0.05%wt. to about 0.8%wt.

One or more insoluble filler materials may also be present in the bar soap compositions. Advantageously such are provided as powders or comminuted particulates of aqueous insolu- ble materials such that due to their small size they are readily incorporated into the compositions from which the bar soaps are produced. These filler materials may be inorganic or organic or a combination as long as it is insoluble in water. The insoluble particles should not be perceived by a user of the bar soap as unduly abrasive or granular and advantageously such filler materials have an average particle of size less than 300 microns, more preferably less than 100 microns and most preferably less than 50 microns. Preferably the insoluble particles have a maximum particle size of 300 microns or less, preferably 200 microns or less.

Non-limiting examples of inorganic particulate materials includes talc and calcium carbonate. Talc is a magnesium silicate mineral material, with a sheet silicate structure and a composi- tion of Mg₃Si₄(OH)22, and may be available in a hydrated form. Talc is considered hydrophobic as it is wetted by oil rather than water. Calcium carbonate or as it is interchangeable referred to as "chalk" exists in three crystal forms: calcite, aragonite and vaterite. The natural morphology of calicite is rhombohedral or cuboidal, acicular or dendritic for aragonite and spheroidal for vaterite. Commercially, calcium carbonate or chalk is also known as precipi- tated calcium carbonate and is produced by a carbonation method in which carbon dioxide gas is bubbled through an aqueous suspension of calcium hydroxide. In this process the crystal type of calcium carbonate is calcite or a mixture of calcite and aragonite. Further non-limiting examples of suitable optional insoluble inorganic particulate materials include alumino silicates, aluminates, silicates, phosphates, insoluble sulfates such as sodium sulfate, borates and clays (e.g., kaolin, china clay) as well as mixtures thereof. Non-limiting examples of organic particulate materials include: insoluble polysaccharides such as highly cross linked or insolubilized starch (e.g., by reaction with a hydrophobe such as octyl succinate) and cellulose; synthetic polymers such as various polymer lattices and suspension polymers; insoluble soaps and mixtures thereof. When present one or more of the foregoing insoluble filler materials may comprise up to about 20%wt. of the bar soap of which it forms a part, but advantageously, when present in included in an amount of from about 0.01%wt. to about 10%wt. Particularly preferred insoluble filler materials and amounts useful in the bar soaps of the invention are disclosed with reference to one or more of the Examples.

The bar soap compositions may include one or more organosiloxane containing constituents, especially polysiloxane containing compounds which may provide a skin treatment benefit to an epidermal surface treated with the bar soap of the invention. Such materials are known per se, and are often interchangeably referred to as silicone emulsifiers. Such silicone emul- sifiers include polydiorganosiloxanepolyoxyalkylene copolymers containing at least one poly- diorganosiloxane segment and at least one polyoxyalkylene segment. The polyoxyalkylene segments may be bonded to the polydiorganosiloxane segments with silicon-oxygen-carbon bonds and/or with silicon-carbon bonds. The polydiorganosiloxane segments of consist essentially of siloxane units which are interlinked by Si-O-Si linkages and which have the formu- la:

R SiO(4{ })/2

The value of b may range from 0 to 3 for said siloxane units with the provision that there is an average of approximately 2, i.e. from 1.9 to 2.1 R radicals for every silicon in the copolymer. Suitable siloxane units thus include R₃SiOi/₂, R2S1O2/2, RSi0₃/₂, and Si0₄/₂ siloxane units taken in such molar amounts so that b has an average value of approximately 2 in the copolymer. Said siloxane units may be arranged in linear, cyclic and/or branched fashion. The R radicals may be any radical selected from the group consisting of methyl, ethyl, vinyl, phenyl, and a divalent radical bonding a polyoxyalkylene segment to the polydiorganosiloxane seg- ment. At least 95 percent of all R radicals are methyl radicals; preferably there is at least one methyl radical bonded to each silicon atom in (d). Divalent R radicals preferably contain no more than 6 carbon atoms. Examples of divalent R radicals include -0-, ~C_mH2_mO-, -C_mH2m - and

--C_mH_2mC0₂ - where m is an integer greater than zero. Illustrative of the siloxane units that make up the polydiorganosiloxane segments are the following, where Me denotes methyl and Q denotes said divalent R radical and bonded polyoxyalkylene segment: R₃SiOi/₂ units such as Me₃SiOi/₂,

Me₂(C₆ H₅)SiOi_/2,

Me₂(CH₃CH₂)SiOi_/2, Me₂QSiOi_/2, MeQ₂ SiOi_/2, Q₃SiOi_/2, Q₂(CH₃CH₂)SiOi_/2, and

Me(C₆H₅)(Q)SiOi/₂ ; R₂Si0_2/2 units such as Me₂Si0_2/2, Me(C₆H₅)Si0₂/₂, Me(CH₂=CH)Si0_2/2, (C₆H₅)₂Si0₂/₂, MeQSi0_2/2, and Q(C₆H₅)Si0₂/₂ ; RSi0_3/2 units such as MeSi0_3/2, C₆H₅Si0₃/₂, CH₂=CHSi0₃/₂, CH₃CH₂Si0₃/₂ and QSi0₃/₂ ; and Si0₄/₂ units.

Volatile linear silicones including polydimethylsiloxane and dimethicones may also be present as silicone emulsifiers in compositions according to the invention.

Also useful as silicone emulsifiers in the inventive compositions are one or more compounds which may be represented by the structure:

wherein

R¹ represents a Ci-C₃₀ straight chained, branched or cyclic alkyl group, R² represents a moiety selected from: (CH₂) -0— (CH₂CHR³0)_m— H

and (CH₂)_n-0— (CH₂CHR³0)_m-(CH₂CHR⁴0)_p-H

in which n represents an integer from about 3 to about 10, R3 and R4 are sleeted from hydrogen and Ci-C₃ straight chain, or branched chain alkyl groups with the proviso that R³ and R⁴ are not simultaneously the same, each of m, p, x and y are independently selected from integers of zero or greater, such that the molecule has a molecular weight of between about 200 to about 20,000,000 and wherein both m and p are not both simultaneously zero, and z is selected from integers of 1 or greater.

When present, one or more of the foregoing organosiloxane containing constituents may comprise up to about 5%wt. of the bar soap of which it forms a part, but advantageously, when present in included in an amount of from about 0.01%wt. to about 1.5%wt. In certain embodiments a organosiloxane containing constituent is necessarily present. Particularly preferred organosiloxane containing constituents and amounts useful in the bar soaps of the invention are disclosed with reference to one or more of the Examples

The bar soap compositions may include one or more optical modifying constituents, such as reflecting materials and pearlizing agents which provide a frequently desirable appearance to the bar soap. Such optical modifying constituents may be inorganic materials, such as one or more of: titanium dioxide, coated micas and other interference pigments; plate like mirror particles such as organic glitters. Further useful optical modifiers may be based on organic materials or compounds, such as one or more of latexes presently commercially available under the trademark ACUSOL (ex. Rohm & Haas Inc.) which are characterized by pH of about 2 to about 3, having approximately 40% solids in water, with particle size of about 0.1 to about 0.5 micron; styrene/polyvinylpyrrolidone co-polymers and styrene/acrylic emulsions, such as styrene/polyvinylpyrrolidone co-polymers available as POLECTRON 430 (ex. ISP Technologies, Inc.), as well as styrene/acrylamide emulsion such as OPULYN (ex. Rohm & Haas Inc.).

The bar soaps may include as optical modifying constituents one or more optical brighteners. By way of nonlimiting examples, such include 4,4'-diamino-2,2'-stilbenedisulfonic acids (fla- vonic acids), 4,4'-distyrylbiphenyls, methylumbelliferones, coumarins, dihydroquinolinones, 1,3-diarylpyrazolines, naphthalimides, benzoxazole, benzisoxazole and benzimidazole systems, and the pyrene derivatives substituted by heterocycles. Specific examples of such optical brighteners include those sold under the trade name TINOPAL (ex. Ciba) such and as TINOPAL CBS which is described to be disodium 2,2'-bis-(phenyl-styryl)disulphonate as well as TINOPAL DMS which is described to be disodium 4,4'bis-(2-morpholino-4-anilino-s-triazin- 6-ylamino)stilbene disulphonate. Such optical brighteners may be included in useful amounts; exemplary useful amounts generally fall within the range on from 0.001%wt. to 0.1%wt.

When present, such optical modifying constituents are advantageously included in generally minor amounts such as from 0.001 - 1 %wt. but desirably are present in amounts from 0.01 - 0.75%wt. In certain preferred embodiments an optical modifying constituents is necessarily present in the bar soaps.

The bar soap compositions may include one or more fragrance materials which may be a one or more compounds which impart an olfactive effect from the bar soap. Exemplary fragrance materials may be based on natural and synthetic fragrances and most commonly are mixtures or blends of a plurality of such fragrances, optionally in conjunction with a carrier such as an organic solvent or a mixture of organic solvents in which the fragrances are dissolved, suspended or dispersed. Such may be natural fragrances, e.g., natural extracts of plants, fruits, roots, stems, leaves, wood extracts, e.g. terpineols, resins, balsams, animal raw materials, e.g., civet and beaver, as well as typical synthetic perfume compounds which are frequently products of the ester, ether, aldehyde, ketone, alcohol and hydrocarbon type, e.g., benzyl acetate, linalyl acetate, citral, citronellal, methyl cedryl ketone, eugenol, isoeu- genol, geraniol, linalool, and Typically it is preferred to use mixtures of different perfume compounds which, together, produce an agreeable fragrance. Other suitable perfume oils are essential oils of relatively low volatility which are mostly used as aroma components. Examples are sage oil, camomile oil, clove oil, melissa oil, mint oil, cinnamon leaf oil, lime- blossom oil, juniper berry oil, vetiver oil, olibanum oil, galbanum oil, labolanum oil and lav- endin oil. When present in a treatment composition, in accordance with certain of the preferred embodiments, the fragrance constituent may be present in any effective amount such that it can be discerned by a consumer of the composition, however is advantageously pre- sent in amounts of up to about 2%wt., preferably are present in amounts of from about 0.00001%wt. to about 1.25%wt. of the bar soap.

The bar soap compositions may include one or more coloring agents, such as one or more dyes and/or pigments, which may be present in effective amounts. Advantageously such one or more coloring agents are present in amounts of about 0.0001 - l%wt. of the bar soap which include said one or more coloring agents.

The bar soap compositions may include one or more vitamins. The compositions of the invention may optionally further comprise one or more vitamins, antioxidants and/or coen- zymes. Nonlimiting examples of vitamins include one or more of Vitamin A and derivatives thereof such as Vitamin A palmitate, acetate, or other esters thereof, as well as Vitamin A in the form of beta carotene, Vitamin C such as ascorbic acid and derivatives thereof including metal salts such as magnesium ascorbyl phosphate, the B vitamins such as thiamine, riboflavin, niacinamide, pyridoxin, and the like, Vitamin E and derivatives thereof such as Vitamin E acetate, nicotinate, or other esters thereof, as well as Vitamin D and Vitamin K. Nonlimiting examples of coenzymes include one or more of thiamine pyrophosphate, flavin adenin dinu- cleotide, folic acid, pyridoxal phosphate, tetrahydrofolic acid, and the like. Nonlimiting examples of antioxidants include one or more of potassium sulfite, sodium bisulfite, sodium erythrobate, sodium meta bisulfite, sodium sulfite, propyl gallate, cysteine hydrochloride, bu- tylated hydroxytoluene, butylated hydroxyanisole, and the like.

When present, such one or more vitamins, antioxidants and/or coenzymes may be individu- ally present in effective amounts, and when present, advantageously comprise at least about 0.001%wt. of the treatment composition of which it forms a part. Preferably, when present, each of the one or more of said vitamins, antioxidants and/or coenzymes comprise from about 0.002%wt. - 0.10%wt. of the bar soap. The bar soap compositions may also optionally include a preservative constituent which is used to control the undesired where the microorganisms within the treatment composition is particularly in long-term storage and at elevated temperatures. Such are usually distinguished from the optional non-cationic compounds which provide an antimicrobial or ger- midical discussed above, as preservative constituents typically are included in minor amounts which are effective in providing a useful benefit to regard spoilage or unwanted microbial growth in the bar soap itself, but are ineffective in providing a useful antimicrobial benefit when dissolved with water to form a washing solution and/or formed into a lather which washing solution and/or lather themselves provided a useful cleaning and/or antimicrobial benefit, particularly to treated dermal surfaces. Thus, such ancillary preservative constituents may be included in minor but effective amounts. Nonlimiting examples include one or more of parabens, including methyl parabens and ethyl parabens, glutaraldehyde, formaldehyde, 2-bromo-2-nitropropoane-l,3-diol, 5-chloro-2-methyl-4-isothiazolin-3-one, 2- methyl-4-isothiazoline-3-one, and mixtures thereof. One exemplary composition is a combination 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one where the amount of either component may be present in the mixture anywhere from 0.001 to 99.99 weight percent, based on the total amount of the preservative. Further exemplary useful preservatives include those which are commercially including a mixture of 5-chloro-2- methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one marketed under the trademark KATHON^® CG/ICP as a preservative composition presently commercially available from Rohm and Haas (Philadelphia, PA). Typically, when present, the preservative constituent is advantageously present in an amount from about 0.00001 - 0.5%wt. of the bar soap.

The bar soap compositions may include one or more antioxidants such as, for example, bu- tylated hydroxytoluene (BHT). One or more antioxidants when present, are advantageously present in any effective amount, e.g., 0.00001% - 0.5%wt. of the bar soap.

The bar soap compositions may include one or more chelating agents. Exemplary useful chelating agents include those known to the art, including by way of non-limiting example; eti- dronic acids and aminopolycarboxylic acids and salts thereof wherein the amino nitrogen has attached thereto two or more substituent groups. Preferred chelating agents include acids and salts, especially the sodium and potassium salts of ethylenediaminetetraacetic acid, di- ethylenetriaminepentaacetic acid, N-hydroxyethylethylenediaminetriacetic acid, and of which the sodium salts of ethylenediaminetetraacetic acid may be particularly advanta- geously used. Such chelating may be included in generally minor amounts such as from about 0.001 - 0.5 %wt. based on the weight of the chelating agents and/or salt forms thereof.

The bar soap compositions may include one or more pH adjusting agents, (which may also be one or more pH buffers) which may be used to establish and/or maintain a desired pH of the compositions from which the bar soaps are formed, as well as to the bar soap itself. Essentially any material which may increase or decrease the pH of the bar soap composition is suitable as a pH adjusting agent. Suitable pH adjusting agents are one or more acids and/or bases whether such be based on organic and/or inorganic compounds or materials. By way of non-limiting example, pH adjusting agents include phosphorus containing compounds, monovalent and polyvalent salts such as of silicates, carbonates, and borates, certain acids and bases, tartrates and certain acetates. Further exemplary pH adjusting agents include mineral acids, basic compositions, and organic acids, which are typically required in only minor amounts. Further exemplary and useful pH adjusting agents include monoalkanola- mines, dialkanolamines, trialkanolamines, and alkylalkanolamines such as alkyl- dialkanolamines, and dialkyl-monoalkanolamines. Such may also function as detersive surfactants. The alkanol and alkyl groups are generally short to medium chain length, that is, from 1 to 7 carbons in length.

By way of further non-limiting example, pH buffering agents include the alkali metal phosphates, polyphosphates, pyrophosphates, triphosphates, tetraphosphates, silicates, metasili- cates, polysilicates, carbonates, hydroxides, and mixtures of the same. Certain salts, such as the alkaline earth phosphates, carbonates, hydroxides, can also function as buffers. It may also be suitable to use as buffers such materials as aluminosilicates (zeolites), borates, alu- minates and certain organic materials such as gluconates, succinates, maleates, citrates, and their alkali metal salts. When present, the one or more pH adjusting agents are included in amounts which are effective in establishing and/or maintaining the pH of a treatment composition at or desired pH value or within a range of pH values. Advantageously the one or more pH adjusting agents comprise from about 0.001 - 2.5%wt., preferably from about 0.01 - 1.5%wt. of the treatment composition of which the one or more pH adjusting agents form a part.

Optionally the bar soap compositions may include one or more skin benefit agents which may be used to promote an improved skin feel, or to improve skin health or appearance, or to promote hair health or appearance. Such include but are not limited to lipids such as cholesterol, ceramides, and pseudoceramides; sunscreens such as cinnamates; other types of exfoliant particles such as polyethylene beads, walnut shells, apricot seeds, flower petals and seeds, and inorganics such as silica, and pumice; additional emollients (skin softening agents) such as long chain alcohols and waxes e.g., lanolin; additional moisturizers; skin-toning agents; skin nutrients such as vitamins like Vitamin C, D and E and essential oils like berga- mot, citrus unshiu, calamus, and the like; water soluble or insoluble extracts of avocado, grape, grape seed, myrrh, cucumber, watercress, calendula, elder flower, geranium, linden blossom, amaranth, seaweed, gingko, ginseng, carrot; impatiens balsamina, camu camu, alpine leaf and other plant extracts such as witch-hazel, and mixtures thereof.

A minor amount of water may be present in the bar soap and the bar soap compositions from which the bar soaps are formed, although such is typically in an amount of not more than 15%wt. is provided to the remaining constituents of a bar soap composition. It is to be realized that in certain of the other constituents, a minor amount of water may be present and may thus be supplied to a bar soap composition from which a bar soap is made; such sources of water are however not considered to be "added water" as defined herein. The overall water content may be up to 12wt.%.

As noted previously, the bar soap compositions described above may be formed into bar soaps according to conventional production methods known to the art. Advantageously the bar soaps are made by a process which involved both the intensive mixing or working of the soap mass while it is in a semi-solid plastic state and its forming into a cohesive mass by the process of extrusion. The intensive mixing can be accomplished by one or more unit operations known in the art which can include roller milling, refining, and single or multistage extrusion. Such processes work the bar soap composition preferably at a tem- perature of between about 20°C and about 70°C to form a homogeneous network of insoluble materials in a viscous liquid and/or liquid crystalline phase containing the lower melting, more soluble surfactants (e.g., soaps and other water soluble/dispersible materials). The extruded mass must be thermoplastic within the process temperature of extrusion which is generally between about 20° C and about 60°C, Thus, the bar soap composition must soften within this process temperature window but remain highly viscous, i.e., not softer excessively to form a sticky mass. The material must regain its structure and harden quickly as the temperature is lowered below its softening point. The softened mass although pliable must be sufficiently viscous so that it does not stick to the surfaces of the extruder in order to be capable of conveyance by the extruder screws but not bend excessively when exiting the ex- truder as a billet. However, if the mass is too viscous it will not be ca pable of extrusion at reasonable rates. The extruded mass of the bar soap compositions may be formed by cutting the extrudate into a final form of a bar soap having defined geometry. The extruded mass may be further optionally formed into a formed bar soa p, such as by sta mping or com- pressing a cut mass of the bar soap composition into a formed th ree-dimensional sha pe having a defined geometry.

By such a process, bar soa ps of the invention may be made. Such extruded bar soa ps have physical-chemical properties and an internal structure which are different from soa ps that are made by a melt-cast process wherein a bar composition is first melted and liquefied in order to form a liq uid phase which is then pou red into molds to solidify by q uiescent cooling, after which the cooled "cast" bars may be removed and used.

Preferably the bar soaps formed form the bar soap compositions are rigid, self- supporting articles having a hardness as measu red using a H u mboldt Model H-1240 electric Penetrometer with a digital automatic ti mer of at least about 1.7 mm, but more preferably (a nd in order of increasing preference) exhibit a hardness of at least: 2, 2.25, 2.5, 2.75, 3, 3.25, 3.5, 3.75, 4, 4.25, and 4.5 mm of needle penetration, preferably as measu red on a single bar soap sample. A single reading, or an average of a plura lity of need le penetration readings (e.g., 2, 3, 5 or more readings), may be used in this eva luation . Again, unexpectedly the bar soap compositions of the present invention are found to be sufficiently d urable for use in forming bar soa ps therefrom by conventional processes, even though preferred bar soa ps comprise in their soap constituent a high weight percentage of C_s - C₁₆, and in particu lar C₁₂ fatty acid soa ps of potassiu m as such lower alkyl distributions in a soap constituent are frequently con- sidered as being too soft for use in a prod uct which is formed into a rigid, th ree-dimensional ta blet or cake, viz., a bar soap, and which also exhibits a usefu l service life after repeated wettings with water. Su rprisingly the bar soa ps of the present invention a re sufficiently hard and provide a satisfactory service life in their product format. Subsequently the bar soaps may be packaged for sale as vendible products, e.g, over- wrapped in a coated paper wrapper, packaged in a box, or even sold without any additional packaging. The bar soaps are used in a conventional manner for personal washing of an mammalian body, e.g, human body and are advantageously used in personal washing, particularly of the epidermis, and hair. When used in a conventional washing process, typically the bar soap is wetted with water, and then contacted with one or more parts of the body, e.g., the epidermis, and hair. A quantity of the bar soap composition is thus eluted into the water and forms a washing composition which provides a useful cleaning and/or microbicidal benefit to the contacted parts of the body. The washing composition when entraining air, may form a lather which is also useful in providing a useful cleaning and/or microbicidal benefit to the contacted parts of the body. Thereafter the washing composition is typically washed or rinsed off the treated parts of the body, e.g., epidermis, hair, with an additional amount of water.

As the bar soaps of the invention are used in a conventional manner, they are used, as well as intended to be used, by contacting a bar soap with a quantity of water, which can be flowing water such as from a faucet, or can be a body (or aliquot) of water such as in a sink, or wash basin. Such contact between the soap bar and the water causes the dissolution or dis- persion of the constituents of the bar soap into the water, viz., and "elution". This elution provides an effective antimicrobial benefit to a topical surface, particularly to the epidermis of a person or animal.

In particularly preferred embodiments, elutions formed from the partial dissolution of a bar soap composition or bar soap in water, which form aqueous dilutions of the bar soaps at concentrations of from 10 - 20 %w/v, (particularly preferably about 10%w/v) exhibit a pH in the range of at least about 9 more preferably a pH in the range of from about 9 - 10, more preferably from about 9.2 - 9.7, with particularly preferred pH values being identified with reference to one or more of the Examples. Desirably such elutions exhibit an antimicrobial benefit, particularly according to the testing protocol described with reference to the Examples.

In particularly preferred embodiments, aqueous compositions (elutions) of 16%wt. bar soap/water, preferably in deionized or distilled water, exhibit at least about a 2.0 loglO reduction of E.coii, S. enterica, K. pneumonia, P. aeruginosa, E. aerogenes, E. faecalis, S. aureus according to ASTM E2315 - 03 "Standard Guide for Assessment of Antimicrobial Activity Using a Time-Kill Procedure". More preferably such aqueous compositions (elutions) exhibit even higher levels of antimicrobial efficacy, preferably (and in order of increasing preference) at least about 2.5, 2.75, 3.0, 3.25, 3.5, 3.75, 4, 4.25, 4.5, 4.75, 5, 5.25, 5.5, 5.75, and even about 6 loglO reduction of according to ASTM E2315 - 03. Specific formulations, specific degrees of antimicrobial efficacy of tested aqueous elutions, according to ASTM E2315 - 03 are demonstrated amongst the Examples. Examples

In these examples the following base formula was used (amounts in the final soap bar)

Function

surfactant Sodium Palmate 60-70

surfactant Sodium Palm Kernelate 12.0

solvent water 11.2

filler salt 0.7

Chelating agent EDTA Na 0.043

Chelating agent Etidronic Acid 0.18

Humectant Glycerin 4.0

solvent water 0.02

Humectant Propylene Glycol 4.0

fragrance 1.3

Dye 0.03 To the mixing bowl of a first blender were added the constituents, which were mixed until they were observed to be homogenous. Thereafter, the contents of the bowl were emptied onto a clean surface, and covered with a plastic food grade film, and a rolling pin was used to manually compress and flatten the mass of the composition. When sufficiently flattened to thickness of between 0.2 - 1 cm, the plastic food grade films temporally removed, and the flattened composition is folded over once or twice, and thereafter the plastic food grade film is of reapplied. Again, rolling pin is used to manually compress and flatten the mass of the composition to the same thickness; this process is repeated between 3-6 times in order to provide improved homogenate distribution of the constituents. Such also mimics the opera- tion of a conventional roll mill provides a similar function. Subsequently, the portion of the flattened composition is cut away, removed, and supplied to a two part die having a cavity. The two parts of the die brought together, under compressive force of approximately 1 ton in order to compress the composition in form it into the final shape of a bar soap. Thereafter, the form bar soaps ejected or otherwise removed from the cavity, and used in the sub- sequent antimicrobial testing as described following. The formed bar soaps had a volume of approximately 50 cubic centimeters and were generally rectangular with radiused edges, each bar having a length of 75 mm, a width of 45 mm and a height of 15 mm.

Antimicrobial Test Protocol:

Each of the following example and comparative example compositions were evaluated for antimicrobial efficacy (as reported as "loglO" reduction of the challenge microorganism on the following tables) against the indicated challenge microorganisms (bacteria).

A testing protocol according to ASTM E2315 - 03 "Standard Guide for Assessment of Antimicrobial Activity Using a Time-Kill Procedure" was used to evaluate antimicrobial efficacy against both Gram positive (Staphylococcus aureus) ( ATTC 6538) and Gram negative (Escherichia coli) (ATCC 10536) bacteria. According to this protocol, first, the challenge bacterial cultu res (18-24 hours) were prepared by suspension in tryptic sodiu m chloride, eq uilibrated to 20 -C - 22 -C at room temperatu re. Where the test composition was a bar soap formed from a bar soap composition, at least half of a bar soap was grated at one time to ensure consistency of the composition . G rating of the bar soap was done using a clean food proces- sor (e.g, KitchenAid, or other) eq ui pped with a suitable blade (e.g, cheese grater) to prod uce small particles or the bar soap. After grati ng, the bar soap particles were transferred to a sterile glass bottle; all such bar soap particles were utilized for testing within 36 hou rs from their grati ng. To form an aq ueous elution for antimicrobial testing, on the day of such testing, a 17.76 gram sample of a composition, e.g, grated bar soap composition (or a commercially available prod uct according to a "comparative example" was combined with 82.24 ml of as sta ndardized hard water sample (300 ppm CaC0₃) at room temperature (20⁹C - 22 -C) in a sterile vessel (e.g, test tube) and stirred, and thereafter the sample was immersed in a 50 -C - 55 -C water bath for 1 - 3 hou rs, d uring which time the sample was periodically removed and sti rred (by swirling the test tube) u ntil all of the composition was fu lly dissolved in the water.

Su bsequently a 9 ml aliq uot of the dissolved composition was dispensed into a sterile cultu re tu be, to which was added 1 ml of the test cultu re, which resu lted in a 16% w/v dilution of the grated bar soap in the water and la rgely aq ueous inoculu m mixtu re. The test tu be was then vortexed for 5 second, and allowed to remain in contact for 60 +/- 5 seconds, immediately after which a 1 ml aliq uot was withdrawn and added to a fu rther tu be containing 9 ml of a neutralizer. The neutralization was allowed to occur for 5 minutes, and thereafter serial tenfold dilutions using tryptic sodiu m chloride were plated, and incu bated for 24-48 hours at 36±1⁹C. The bacterial inocu la used were also seria lly diluted, plated and incu bated for 24-48 hou rs at 36±1⁹C. Post-incu bation the su rviving colony-forming u nits (CFUs) of the challenge bacteria were en umerated and logio red uction values for each formu lation tested were determined from one or more replicate samples, in the case of plura lity of replicate samples the average resu lts were reported. The results of this testing is shown below.

Product Contact Time Organism Log Red. (avg)

Base

+ 0.7% TCC

60 sec E. coli >5.51

+ 0.3% PCMX

+ 1.0% Lemongrass Product Contact Time Organism Log Red. (avg)

Base

+ 0.7% TCC

+ 0.3% PCMX 60 sec E. coli >5.49 + 3.5% PEG12

+ 1.0% Lemongrass

Product Contact Time Organism Log Red. (avg)

Base

+ 0.7% TCC

60 sec E. coli 2.34

+ 0.3% PCMX

+ 0.075% Geraniol

Product Contact Time Organism Log Red. (avg)

Base

+ 0.7% TCC

60 sec S. aureus 2.68

+ 0.3% PCMX

+ 1.0% Goldenseal Oil

60 sec E. coli 2.40

Claims

1. A semi-translucent bar soap composition provides an effective antimicrobial benefit against gram positive and gram negative bacteria, which bar soap compositions comprises: a) u p to l%wt. of an antimicrobial system which comprises lemon grass oil.

b) at least 55% of salts of Ci₂, C_i4 ,C₁₆ and Cig saturated fatty acids.

c) a non-q uaternary ammoniu m based germicidal compou nd .

2. A composition according to claim 1, wherein the non-quaternary ammoniu m based germicidal compound is present at a level of 0.1 to 5wt%, preferably about lwt%.

3. A composition according to claim 2, wherein the non-quaternary ammoniu m based germicidal compound comprises chloroxylenol and / or tricloca rban .

4. A composition according to claim 1, 2 or 3, wherein the bar soap composition is characterized in exhibiting a red uction of Klebsiella pneu moniae.

5. A composition according to claim 4, wherein the bar soap composition is cha racterized in exhibiting at least a 3 log 10 red uction of Klebsiella pneu moniae when tested accord- ing to the sta ndardized test protocols of ASTM E I 053 Sta ndard Test Method to Assess Virucidal Activity of Chemicals I ntended for Disinfection of I nanimate, Non porous Environ mental Su rfaces.

6. A method for providing a germicidal benefit to a topical su rface, especially a dermal su rface, the method comprising the step of: contacting a topical su rface u pon which the presence of one or more u ndesired pathogens, preferably bacteria, are known or suspected, with a bar soap composition according to any one of claims 1-5.