IE41913B1 - Shampoo compositions - Google Patents

Abstract

The clear homogeneous hair shampoo has conditioning and antimicrobial properties and contains a complex of a polyalkyleneimine with a heavy metal salt of 2-pyridinethiol 1-oxide and at least one surfactant. The polyalkyleneimine is the product of the polymerization of an imine of the formula I with a degree of polymerization not exceeding 1500, in which R<3> and R<4>, which are identical or different, are hydrogen or alkyl groups with 1 to 6 carbon atoms. The surfactant or the surfactants are a) a sulphated ethoxylated amine of the formula (II) in which R<1> is an alkyl or alkenyl group with 8 to 18 carbon atoms, R<2> is hydrogen or an alkyl or alkenyl group with 8 to 18 carbon atoms, b is an integer from 1 to 15, and X is the ion of an alkali metal, and/or b) a sulphated ethoxylated amide of the formula (III) or (IV> R<1>-CO-NH-(Y)a-(CH2CH2O)bSO3X (III> or in which Y is an unbranched or branched alkyleneoxy group with at least 2 carbon atoms, a is 0 or 1, c is an integer from 1 to 14, and d is an integer from 1 to 14, where the total of c and d does not exceed 15.

Description

The present invention relates to shampoo . compositions arid in particular to shampoo compositions for combatting dandruff which have conditioning properties.

Various combinations of detergents and 5 conditioning agents have been proposed in attempts to produce a single phase liquid shampoo composition which will both cleanse and conditiop the human hair,and be effective against dandruff. Hitherto however, the need to meet the many requirements of a satisfactory liquid shampoo composition have made if difficult for such 1θ attempts to succeed.

As regards the cleansing and conditioning effects, it is generally considered desirable in that such . liquid compositions, should clean the hair., produce a foam which is persistent in the presence of grease but which can be removed by l rinsing the hair with water, leave the 'hair lustrous and pleasant to touch, possess an adequate shelf-life and impart a conditioning effect to the hair. By the term conditioning effect or improvement in hair condition as used herein is meant an improvement in the manageability of the hair which may be signified- by one or more of the following results being obtained:(a) an improvement in the ease of combing of wet and dry rinsed hair, Cb) an increase in the softness of the hair to the touch, (c) a reduction in the tendency of the hair to tangle, (d) a reduction in the tendency of the hair to acquire a charge of static electricity and 2. (e) an apparent increase in gloss.

Polyolefin imines, (and in particular polyethylene imine) have been suggested as conditioning agents for use in shampoo compositions.

Various anti-microbial agents have been proposed in an attempt to produce compositions effective against dandruff. In particular, zinc 2-pyridinethiol-l-oxide, hereinafter referred to as zinc pyrlthione or ZPTO has been proposed as an anti-microbial agent. This salt, however, is extremely insoluble in water ( of the order of 10-20 ppm at pH7), and attempts to formulate it into shampoo compositions have led to suspension-type preparations containing particulate material. The use of co-solvents such as ethanol has been proposed in order to solubilise ZPTO, but the presence of ethanol in compositions for the hair is undesirable, as it extracts intercellular material, and weakens the hair.

It is known that polyethylene imines have a strong chelating action, and will form complexes with ZPTO, and attempts have been made to incorporate ZPTO/polyethylene imine complexes into shampoo-type compositions. These attempts have resulted either in formulations containing suspended solids, or at best in formulations which although initially clear, are unstable and form deposits on storage.

The specification of Patent Specification Ho. describes how certain classes of cationic conditioners can be solubilised in shampoo compositions containing such conditioners together with a detergent, by choosing a particular class of detergent. Claim 1 of Patent Specification 3. · 41813 No. rea(3s A cosmetical shampoo composition which comprises at least one detergent which is a sulphated fatty amine, fatty acid amide or fatty acid alkanolamide or a sulphated ethoxylated fatty amine, fatty acid amide or fatty acid alkanolamide having a mean ethoxy group content of up to 15 ethoxy groups per mole and wherein the hydrocarbon chains in the fatty or fatty acid moiety each contain from 8 to 18 carbon atoms, or a Salt thereof, and at least one cationic conditioner (as hereinbefore defined) dispersed in an aqueous medium, the pH of the composition being in the range of from 4 to 7.

We have now found that when the detergents used in Patent Specification No. p use<i with the ZPTO/polyethyleneimine complexes mentioned above. A clear aqueous shampoo composition can be produced (i.e. one whioh does not deposit any solid material on centrifuging) which Is storage stable. Clear compositions are generally preferred by the consumer. In addition it has been discovered that in the clear compositions of the invention, the ZPTO is up to 4 times as effective as in the previously known suspension formulations. lhe invention provides a clear, homogeneous shampoo cotposition which comprises, in an aqueous medium, at least one detergent which is a sulphated aliphatic amine, amide, or alkanolamide, or a sulphated ethoxylated aliphatic amine, amide or alkanolamide having a mean ethoxy group content of up to 15 ethoxylate units per mole, a cationic conditioner which is a polymer, having an average degree of polymerisation of from 5 to 1500, of an imine of the formula: 4. 41813 R R _I_I _ I II 4 wherein R and R are each independently a hydrogen atom as a C| to Cg alkyl group, or an alkoxylated derivative of such a polymer, and a quantity of zinc 2-pyridinethiol-1-oxide complexed with the cationic conditioner, the carbon chain of the aliphatic moiety of the detergent having a chain length of from 8 to 18 carbon atoms.

The amine-based detergents whioh are used in the shampoo compositions of the present invention are truly amphoteric in nature, whilst the amide- and alkanolamidebased detergents generally have lower anionic character than conventional anionic detergents at any particular pH.

The detergents derived from the amine, amide, alkanolamide or alkoxylated derivative thereof may be prepared by processes which involve a sulphation or sulphamation reaction. Generally a sulphamation reaction, for example using sulphamic acid or an alkyl sulphamic acid, is more applicable to the preparation of amine-based detergents than amide or alkanolamide-based detergents . 41813 because the milder sulphamation reaction is more generally of use since the amines from which the detergents are derived are more labile bases than the corresponding amides or alkanolamides. The amide- and alkanolamide-based detergents may be prepared using a sulphation reaction, for example with sulphur trioxide or chiorosulphonic acid. Under suitable reaction conditions, however, either reaction is applicable to any of the starting materials.

The amine-based detergents used in the shampoo compositions of the present invention may generally be represented by one of the formulae: R - NH - (CILCH„O).SO,X (I) or 2 2 'b 3' (XI) . 1 2 wherein R, R and R are each independently an alkyl or alkenyl group containing from 8 to 18 carbon atoms 5 b is an integer from 1 to 15 and X is a hydrogen atom, an ammonium or quaternary ammonium cation or the ion of an alkali metal or alkaline earth metal. Preferably the groups 1 2 R, R and R will each contain from 12 to It carbon 1 2 atoms, the groups R and R in Formula II being the same or different.

Examples of typical reactions which may be 6. 41813 used in the production of the amine based detergents are - given below: (i) R - NH2 + HS03NH2 —> R-nh. - SO^NHj/ (ii) R - NH - (GHgCH O^H + HSO NH __v 2 / R - NH - CCHgCHgO^ScrNH* (Hi) r2 1 R - N - (CH CH Ο) H + HSO NH v Λ D 3 2 ........ Z R2 R1 - N - CCHaCHsO)bSO~NH* It will be appreciated that by using an alkyl 10 substituted sulphamic acid instead of sulphamic acid, an amine salt instead of an ammonium salt is obtained. The alkali metal and alkaline earth metal salts may be prepared for example via cation exchange by reacting an appropriate ammonium salt with a strong base. A sodium salt may thus be prepared by the treatment of an ammonium salt with sodium hydroxide.

The amide-and alkanolamide-based detergents used in the shampoo compositions of the present invention may generally be represented by one of the formulae: 7. 41813 R - CO - NH 0Oa - (CH2CH2O)bSO3X (III) (Oa-(CHaCH2o)cso3x R-CON (IV) COa-(CH2CH2O)dSO3X wherein R is an alkyl or alkenyl group containing from 8 to 18 carbon atoms; b is an integer from 1 to 15; X is a hydrogen atom, an ammonium or a quaternary ammonium cation, or the ion of an alkali or alkaline earth metal; Y is a straight chain or branched chain alkoxy group containing 2 or more carbon atoms; a is 0, of 1; c is an integer from 1 to 14; d is an integer from 1 to 14; ί and the sum of c and dis not more than 15, Preferably the group R contains from 12 to 14 carbon atoms.

Examples of typical reactions which may be used in the preparation of amide- and alkanolamide-based detergents are given below: 8. 41813 (tv) R - CONHCkLCH OH + SO -->R - CONHCH-CH OSO.H Q d NH V - + RCONHCHgCHgOSOgNH^ (v) RCONHCHgCHgOCCHgCHgO) H + SOQ--> product NaOH RCONHCHgCHgOiCHgCHgO^SOgNa* (vi) RCONHCHgCHOCCHgCHgO^H + HSO^NHg -=j I ~ 4RCONHCH0CHO(CH_CH00> SOo NHj d ci d D 3 *l· (vS).

(CH CH Ο) H I 2 2 0 RCO-N· <CH2CHS°>dH NaOH RCO-N (CH CH O) SO~Na+ 9. 41813 The conversion to the sulphated detergent in the above reaction may not be complete. The percentage conversion is usually in the range from 50 to 100$. When the starting material is an alkanolamide there is no necessity to remove the unreacted starting material since the unreacted alkanolamide will act as a foam stabiliser in the shampoo composition.

The chain length of the aliphatic moiety of the detergent is preferably that found in nature in coconut oil or palm kernel oil, that is chiefly a chain length of 12 carbon atoms, but the starting materials may also be of synthetic origin.

The ethoxy group content in the ethoxylated amine-, amide- and alkanolamide-based detergents used in the composition of the present invention may be up to 15 ethoxylate units per mole. Preferably however detergents with a mean ethoxy group content of from 1 to 6 units per mole are used. The desired mean ethoxy group content may be obtained by blending two or more detergents having different ethoxylate chain lengths.

The total level of detergent in the shampoo compositions of the present invention may be varied in accordance with the degree of foaming and cleansing desired. It will generally be in the range of from 5 to 35$, preferably from 10 to 30$ by weight of the total composition. The amine, amide or alkanolamide based detergent may be partially replaced by an additional detergent, but such additional detergent preferably .

V 41813 constitutes less than 50% of the total detergent. Additional detergents Which may be used are amphoteric detergents, 'for example, alkyl betaines, such as lauryl betaines, amide oxides such as alkyl dimethyl amine oxide and imidazolines, or anionic detergents such as salts of lauryl ether sulphate for example, the sodium or monoisopropanolamine salts.

The imine polymers used in the compositions of the present invention have been reported (J. Soc. Cos.

Chem. 23, 593-603 (1972)) to have a structure which may be represented as:- R3- CH r3 r1* > I I 1 -CH - CH - NH - 4 / 1 - J «3 rA t ' I CH - CH - NHg where m has a value such that the polymer has a degree of polymerisation of from 5 to 1500 preferably from 5 to 100 15 and R3 and R4 each represents an H atom or an alkyl group having from 1 to 6 carbon atoms. They may be prepared by the polymerisation of an imine of the formulasR3 R4 I I H-C - C-H \»/ I H wherein and R are as defined above.

In practice a considerably amount of branching occurs in the polymerisation of imines and primary, secondary and tertiary 11. θ 13 nitrogen atoms will be present in the molecule. The imine polymers may be alkoxylated by reaction with an alxylene oxide.

The cationic character of the imine polymer increases as the acidity of the medium in which it is placed increases. In the above mentioned paper it is reported that at pH 8.0, pH 6.0 and pH 4.0 the percentage of nitrogen atoms in polyethyleneimine having a positive charge is 25$, 33$ and 50$ respectively.

Examples of ethyleneimine polymers which are produced by the Dow Chemical Co. (Midland Mich 48640), are as follows: Trade Name PEI 6 PEI 12 PEI 18 PEI 600 PEI 600 E Polyethyleneimine M.W. 600 Polyethyleneimine M.W. 1200 Polyethyleneimine M.W. l800 Polyethyleneimine M.W. 60,000 Polyethyleneimine M.W. 60,000 reacted with ethylene oxide in ratio 1 : 0.75 The imine polymer used as cationic conditioner may be used in the compositions of the present invention in an amount of active ingredient from 0.05 to 2.5$ by weight of the total composition, preferably from 0.1 to 1.0$ by weight.

Cationic conditioners are substantive to human hair, an effect believed to be due to electrostatic attraction. During use of the composition of the invention the conditioner is adsorbed as a thin continuous film over 12. 41Θ13 the hair to provide a conditioning effect on the hari. The adsorption of the cationic conditioner by this mechanism achieves a total or almost total coverage of each hair with a thin film of the conditioner. The film of conditioner may be as thin as one monolayer and still exert a conditioning effect on the hair.

In addition to its conditioning effect polyethyleneimine shows strong anti-microbial action against several organisms. In particular it has been shown that polyethyleneimine has a powerful inhibitory action against the organism P. ovale which is reported to be associated with dandruff. Other anti-microbial agents such as 2, 4, 4'trichloro-2'-hydroxy diphenyl ether (Irgasan DP 300 - Ciba-geigy Irgasan is a Registered Trade Mark), trichlorocarbanilide, cetyltrimethyl ammonium chloride, benzalkonium chloride, or colloidal sulphur may be included in the shampoo compositions of the present invention.

Zinc pyrithione is also used as an anti-microbial agent in the composition of the invention, in the form of a complex thereof with an excess of polyethyleneimine.

The shampoo compositions of the present invention may contain up to 0.5% by weight of zinc pyrithione (calculated as ZPTO), complexed with the imine polymer.

The preferred pH of the shampoo composition will depend upon the particular formulation. A decrease in pH enhances the cationic character of the shampoo composition. Accordingly, the preferred pH of the compositions will be as low as possible, provided that the resulting composition shows the necessary stability, and meets the 13. 41813 normal safety requirements for shampoos. The preferred pH is generally as low as possible within the limitations of product stability and safety, and usually within the range 4 to 10. The preferred pH of the composition does however vary according to the molecular weight of polyethyleneimine and the detergent system used. For example in compositions using the sodium salt of sulphated 1.9 mole ethoxylated coco fatty acids monoethanolamide and coco dimethyl betaine detergents, the preferred pH range of the compositions is 8.5 to 9, whereas in compositions using a detergent mixture containing the ammonium salt of sulphated cocoamine, the sodium salt of sulphated 6-mole ethoxylated coco amine, and coco dimethyl betaine the preferred pH range is 5 to 7.

The pH of the composition may be adjusted to the required value by the addtion of acid, the preferred acids being phosphoric acid, hydrochloric acid, acetic acid, sulphuric acid, tartaric acid and citric acid, or by the addition of a base such as sodium hydroxide or triethanolamine or monoisopropanolamine.

Additional cationic conditioners may be incorporated into the shampoo compositions of the present invention in an amount from 0.1 to 10% preferably 0.1 to 2.5% by weight of the total composition. The additional cationic conditioner may be a mono- or poly- cationic compound or a mixture thereof.

Examples of mono-cationic compounds which may be used in the compositions of the invention are: alkyl trimethyl ammonium halides, N-alkyl pyridinium halides, N-alkyl isoquinolinium halides, di-alkyl dimethyl ammonium halides, alkyl aryl dimethyl ammonium halides, fatty acid aminoalkyl amines sold under the 14. 41813 trade name Sapamines (Trade Mark) and alkyl benzyl hydroxy ethyl imidazolinium ohloride.

Mixtures of suoh compounds may also be used.

In order to improve the solubility of suoh mono cationic oompounds the nitrogen groups may be ethoxylated. This is particularly important in the case of dialkyl quaternary ammonium salts whose solubility in an aqueous medium is low.

Examples of typical polycationic compounds which may be used in the compositions of the invention are: high molecular weight aminoethyl acrylate/ phosphate/acrylate copolymer sold under the trade 15 name CATREX (formerly known as RESYN 78-3510) National Adhesives Limited. quaternised vinyl pyrollidone copolymers sold under the trade name GAP'QUAT e.g. GAP’QUAT 73^, 755, 750 or 759 by G.A.F. Limited, the low molecular weight condensation product of adipic acid, diethylene triamine polyamide and epichlorhydrin sold under the trade name DELSETTE e.g. DELSETTE 101 or 201 by Hercules Limited and, the quaternary nitrogen containing cellulose ether sold under the trade name POLYMER JR by Union Carbide Corporation. Mixtures of such compounds may also be used. (RESYN, CATREX, GAP’QUAT, DELSETTE and POLYMER JR are Trade Marks). Ϊ5.

The shampoo compositions of the present invention may contain additives which are common in contemporary shampoo preparations, provided that such additives do not interfere to any significant extent with the mechanism of adsorption of the cationic conditioner onto the hair and do not significantly decrease the effectiveness of any anti-microbial agent present.

Non-ionic foam stabilisers typically used in shampoo preparations may be incorporated into the shampoo compositions of the present invention. Typical examples of foam stabilizers are amine oxides, such as coco dimethyl amine oxide, alkyl betaines such as coco dimethyl betaine, alkanolamides such as the monoethanolamide and diethanolamide of coco fatty acids or their ethoxylated derivatives. The foam stabilizers are generally incorporated in the composition of the present invention in an amount of from 1 to 5$ by weight based on the weight of the total composition.

Thickeners, such as simple salts or ethoxylated fatty acids or thinners, such as glycols, polyglycols or polyalkylene glycols may be incorporated into the compositions of the invention.

Further additives such as protein hydrolysates, lanolin and derivatives thereof, herbal or balsamic extracts, yitamins, vegetable oils, dyes, perfumes and preservatives, such as formalin or dodecyl guanidine, may be incorporated without impairing the fundamental px’operties of the compositions. 16. 41813 Pearlising or opacifying agents may also be added, for example ethylene glycol monostearate, ethylene glycol distearate, alkaline earth metal soaps or fatty alcohols.

The following Examples further illustrate the present invention. Percentages are percentages by weight based On the total weight of the composition unless otherwise stated.

Example 1 In preparing the following composition the zinc pyrithione was mixed with the PEI 6 and some of the water.

The clear solution obtained was then blended with the remaining ingredients in a simple mixer: Sodium salt of sulphated 1.9 % w/w mole ethoxylated coco fatty acids monoethanolamide (30% aqueous solution) predominantly of the formula: rconhch2ch2o(ch2ch2o)gSOjNy 65 Coco dimethyl betaine (30% aqueous solution) 10.0 POLYMER JR 400** 0.2 Zinc Pyrithione 0.25 Polyethyleneimine (MW 600) 0.47 Colour, perfume, preservative q.s. Water to 100 **POLYMER JR 400 a polycationic polymer supplied by Union Carbide. (a) The conversion to sulphate in the manufacture of this detergent was 75% effective and hence the 30% aqueous solution contains 24% sulphate and 6% unreacted 1.9 mole ethoxylated coco fatty acids monoethanolamide. 17, In the above fonnula for the detergent, R represents the mixture of chain lengths found in the alcohols of coconut oil which varies depending upon the source, method of extraction and subsequent treatment. Chain length analysis of the oil content of coconut generally falls within the extremes:Cθ 5.4-10.4; C1Q 4.5-14.4; C12 44.1-51; C14 13.1-18,1%; ^16 7.5-9.6%; C^g 1.3-3.2%; Onsaturateds at C^g are 5-23.7%. The most commonly occurring figures ares- Cg 7.7-9.5%; C1Q 5.5-9.7%; C12 37.1-51.3%; C14 7.1-18.5%; C15 1.8-10.5%; Clgl.O-3.7%; and unsaturateds at C^g 5.5^8.2%. On conversion to fatty amides (from which the ethoxylated sulphates are produced), one carbon atom of the aliphatic chain is converted to the carbon atom of the amide group, and the resulting distribution of values for R given by the manufacturers, Albright and Wilson Marchon Division is:- Cy 3-7%; Cg 2-6%; C^^ about 48%; C^3 about 15%; C^g about 7-12%; C-^γ about 17-23% (inclusive of unsaturated).

It is not possible to achieve pure products on a commercial scale during conversion to amides or subsequent ethoxylation and there is present in the material used a mixture of secondary and tertiary amides in which the secondary amide predominates.

The pH was adjusted to 8.6 by addition of hydrochloric acid.

The resulting shampoo was a clear composition which did not deposit any particulate material during storage or after prolonged Centrifuging. 18. 41813 This product was tested for bacteriostatic activity against Staph.aureus, E.coli and P.ovale. The average minimum inhibition dilutions were measured, and a further test was carried out, to examine substantivity. In this test, a calf skin disc was soaked in a diluted solution of the shampoo composition for five minutes at 37°C. It was then removed, rinsed thoroughly, placed on an agar plate, and incubated. The zones of inhibition were measured in mm.

The results were as follows :Average Minimum Inhibition Dilution Staph.aureus E.coli P. ovale in 800 1 in 315 1 in 2400 Calf skin inhibition Zone ln mm.

Staph.aureus P.ovale (dilution 1 in 10) (dilution 1 in 4) mm 16 mm The results show a strong inhibitory action against P.ovale and a high degree of substantivity.

The composition of Example 1 has also been subjected to an antidandruff trial on a panel of 24 people. The procedure was to use a panel of four trained observers to visually assess the dandruff level of subjects every week prior to shampooing, and to record the degree of severity measured on an arbitrary scale. A control shampoo was used for the first five weeks of the trial and then the composition of Example 1 was used for the next ten weeks. The reduction in dandruff level was marked reaching a maximum after eight weeks treatment with the composition of Example 1. The reduction in dandruff was greater than was achieved in a parallel trial conducted under similar conditions using a zinc pyrithione shampoo available on the market containing four times the zinc pyrithione level (1%) in suspension form. 19. 41813 Example 2 The following composition was prepared, in a similar manner to the composition of Example 1. $ w/w Sodium salt of sulphated 1.9 mole ethoxylated coco fatty acids monoethanolamide (30$ aqueous solution) as in Example 1 45.0 Coco dimethyl betaine (30$ aqueous solution) 10.0 TEXAPON IES** 10.0 Zinc pyrithione 0.25 Polyethyleneimine (MW 600) 0.47 Sodium Chloride 3.0 Colour, perfume, preservative q.s.

Water to 100 ** a commercial anionic surfactant supplied by Henkel Limited, containing the alkanolamine salt of fatty alcohol ether sulphate containing nominally 60$ active detergent.

The pH of the composition was adjusted to 8.55 by addition of hydrochloric acid. The resulting shampoo was a clear composition which does not deposit any particulate material during storage or after prolonged centrifuging.

The product was tested for bacteriostatic activity in a similar manner to that described in Example 1.

The results obtained were:Average Minimum Inhibition Dilution Staph, aureus E.coli P ovale in 3200-6400 1 in 800 1 in 3200-6400 . 41813 Calf Skin Inhibition Zone in mm Staph.aureus P.ovale (dilution 1 in 10) (dilution 1 in 4) mm 17 mm Example 3 The The following composition was prepared in a similar manner to the composition of Example 1.

Sodium salt of sulphated 6 mole ethoxylated coco amine (30% solution) predominantly of the Ιθ formula: RNH(CH2CH2O)gSOjNg Ammonium salt of sulphated coco amine of formula (50% paste) RNHSO3NH4 (50% paste) Coco dimethyl betaine (30% aqueous solution) Zinc pyrithione Polyethyleneimine (MW 600) Perfume, colour, etc.

Water up to 100 N.B, The footnote to Example 1 regarding the value 20 of R, and degree of ethoxylation also applies to the detergents used in this Example, (the conversion to sulphate is 75% effective).

The pH of the composition was adjusted to 6.4 by the addition of citric acid. The resulting liquid shampoo composition was clear.

Examples 4 to 6 Three compositions were prepared containing the constituents listed below. 60.0 .0 .0 0.25 0.47 q.s. 21. 41813 $ by weight Example Example 4 5 Example 6 Sodium salt of sulphated 1.9 mole ethoxylated coco monoethanolamide as in Example 1 55 55 55 coco dimethyl betaine (30$ solution) 12.50 12.50 12.50 monoisopropanolamine salt of 2 mole lauryl ether sulphate (28$ active) 16.50 16.50 16.50 monoisopropanolamine lauryl sulphate (35$ active) 4.40 4.40 4.40 mono is opropanolamine 3.00 3.00 3.00 zinc pyrithione 0.25 0.25 0.25 polyethyleneimine (MW 600) 0.44 - - polyethyleneimine (MW 1200) - 0.50 - polyethyleneimine (MW 1800) - - 0.75 Colour perfume q.s. q.s . q.s. Water to 100 to 100 to 100 The compositions of Examples 4 to 6 were prepared in a similar manner to that described in Example ‘.1.

The pH of each of these Examples was adjusted to 8.7 by the addition of sulphuric acid. All gave clear shampoos which were tested for bacteriostatic activity as described in Example 1. The results obtained were Ayerage Minimum Inhibition Dilution Staph.aureus E.coli p.ovale Example 4 1 in 1600 1 in 800 1 in 2000 Example 5 1 in 800 1 in 400 1 in 2000 Example 6 1 in 800 1 in 400 1 in 2000 22 41813 Calf Skin Inhibition Zone in mm Staph, aureus E.coli' P.ovale Example 4 23 20.5 16 Example 5 21 20 16 5 Example 6 20.5 19 16

Claims (19)

1. A clear, homogeneous shampoo composition, which comprises, in an aqueous medium, at least one detergent which is a sulphated aliphatic amine, amide, or alkanolamide, or a sulphated ethoxylated aliphatic amine, amide or alkanolamide having a mean ethoxy group content of up to 15 ethoxylate units per mole, a cationic conditioner which is a polymer, having an average degree of polymerisation of from 5 to 1500, of an imine of the formula: R 3 R 4 I I H-c-C —- H I H 3 4 wherein R and R are each independently a hydrogen atom -.or a to Cg alkyl group, or an alkoxylated derivative of such a polymer, and a quantity of zince 2-pyridinethiol-1-oxide complexed with the cationic conditioner, the carbon chain of the aliphatic moiety of the detergent having a chain length of from 8 to 18 carbon atoms.

2. A shampoo composition as claimed in claim 1 wherein the detergent is an amine based detergent having the fonnula:R - NH - (CH 2 CH 2 O) b SO 3 X or r 2 1 I R - N - (CH 2 CH 2 O) b SO 3 X 1 2 wherein R, R and R are each individually an alkyl or alkenyl group containing from 8 to 18 carbon atoms; b is an integer from 1 to 15; and X is a hydrogen atom, an ammonium or a 24. 41813 quaternary ammonium salt cation, or the ion of an alkali metal or alkaline earth metal.

3. A shampoo composition as claimed in claim 1 ° 2 wherein each of the groups R, R and R u contains from 12 to 14 carbon atoms.

4. A shampoo composition as claimed in claim 1 wherein the detergent is an amide or alkanolamide based detergent having the formula: R - CO - NH (Y} a - (CH g CH 2 O) b SO 3 X °r (ρ & -(ΟΗ 2 ΟΗ 2 Ο) σ 3Ο 3 Χ R-CON I (Υ) 3 -(ΟΗ 2 ΟΗ 2 Ο) ά5Οθ Χ wherein R is an alkyl or alkenyl group containing from 8 to 18 carbon atoms; b is an integer from 1 to 15; X is a hydrogen atom an ammonium or quaternary ammonium salt cation, or the ion of an alkali or alkaline earth metal; Y is a straight chain or branched chain alkoxy group containing 2 or more carbon atoms; a is 0, or 1; c is an integer from 1 to 14; 25. ί d is an integer from 1 to 14; • and the sum of c and d is not more than 15.

5. A shampoo composition as claimed in claim 4 wherein the group R contains from 12 to 14 carbon 5 atoms.

6. A shampoo composition as claimed in any one of the preceding claims wherein the mean ethoxy group content of the detergent is from 1 to 6 ethoxylate units per mole. 3

7. · A shampoo composition as claimed in any one of the preceding claims Wherein the desired mean ethoxy group content is obtained by blending two or more detergents having different ethoxy group contents.

8. A shampoo composition as claimed in 15 any one of the preceding claims which comprises in addition an additional detergent, the additional detergent constituting less than 50? by weight of total detergent.

9. A shampoo composition as claimed in any one of the preceding claims wherein the total amount of detergent in the shampoo is from 5 to 55? by weight of the total composition.

10. A shampoo composition as claimed in 26. 41813 claim 9 wherein the total amount of detergent in the shampoo is from 10 to 30% by weight of the total composition.

11. A shampoo composition as claimed in any one of the preceding claims wherein the average degree of 5 polymerisation of the polymer is from 5 to 100.

12. A shampoo composition as claimed in any one of the preceding claims wherein the total amount of free and complexed imine polymer or alkoxylated derivative thereof in the composition is from 0.05 to 2.5% by weight £0 of the total composition.

13. A shampoo composition as claimed ih claim 12 wherein the total amount of free and complexed imine polymer or alkoxylated derivative thereof is from 0.1 to 1.0% by weight of the total composition.

14. 15 14. A shampoo composition as claimed in any one of the preceding claims, which contains a total of up to 0.5% by weight of complexed zinc pyridinethiol-l-oxide, calculated as zinc pyrldinethiol-1-oxlde. 15. A shampoo composition as claimed in any one 20 of the preceding claims wherein an additional cationic conditioner is present in an amount from 0.1 to 10% by weight of the total composition.

15. 16. A shampoo composition as claimed in claim 15 27. wherein the additional cationic conditioner is present in an amount from 0.1 to 2.5% by weight of the total composition.

16. 17. A shampoo composition as claimed in any one of the preceding claims which addtionally comprises, as an 5 antimicrobial agent, 2, 4, 4'trichloro-2Shydroxy diphenyl ether, trichlorocarbanilide, cetyltrimethyl ammonium chloride, benzalkonium chloride, or colloidal sulphur.

17. 18. A shampoo composition as claimed in any one of the preceding claims which additionally includes at least 10 one of a foam stabilizer, a preservative, a thickfier, a Λ perfume, a colourant or a pearlising or opacifying agent.

18.

19. A shampoo composition as claimed in claim 1 substantially as hereinbefore described with reference to any one of the Examples.