WO1996021721A1

WO1996021721A1 - Concentrated, aqueous, surfactant-containing compositions

Info

Publication number: WO1996021721A1
Application number: PCT/GB1996/000058
Authority: WO
Inventors: Michael Harris; Nigel Frederick Cooper; Clare Ewin; John Marshall
Original assignee: Jeyes Group Ltd
Current assignee: Jeyes Group Ltd
Priority date: 1995-01-12
Filing date: 1996-01-12
Publication date: 1996-07-18
Anticipated expiration: 1997-07-12
Also published as: AU4394496A; GB9500577D0

Abstract

An aqueous, surfactant-containing, concentrate which on dilution with water gives a diluted liquid of the same or increased viscosity, the composition comprising: (a) up to 15 % by weight of a surfactant component consisting of one or more anionic surfactants alone or in combination with one or more nonionic or amphoteric surfactant; (b) an electrolyte or hydrotrope; and (c) water.

Description

CONCENTRATED, AQUEOUS, SURFACTANT-CONTAINING COMPOSITIONS

This invention is concerned with improvements in and relating to liquid compositions and, more especially, to concentrates for dilution, with water, to produce liquid surfactant-containing compositions.

It is well known to provide so-called "thick" or "thickened" liquids compositions, that is compositions with generally increased viscosity, for application to surfaces. Such thick compositions have the advantage that, by virtue of their viscosity, they tend to remain in contact with vertical or inclined surfaces or other substrates for a longer period of time than do more mobile compositions. Thickened compositions may also be poured in a controlled manner and are generally aesthetically appealing.

It is also known to provide precursors for liquid cleansing or like compositions (such as fabric softener compositions, all purpose cleaners, bleaches and washing up liquids) in the form of liquid concentrates to be diluted with water, to the desired concentration, by the user. However, on dilution with water, thick concentrates tend to become thinner, ie. reduce in viscosity. We have found that certain liquid concentrates for a thickened composition may be formulated in such a manner that their viscosity remains the same or, preferably, increases on dilution with water, e.g. so as, when diluted with water in a ratio of water to concentrate of at least 1:1, e.g. to give a viscosity of at least 50 cp at 25^βC.

According to the invention there is provided an aqueous, surfactant-containing concentrate which, on dilution with water, gives a diluted composition having a viscosity the same as or greater than that of the concentrate, which concentrate comprises: - (i) up to 15% by weight of a surfactant component consisting of one or more anionic surfactants alone or in admixture with one or more nonionic or amphoteric surfactants; (ii) an electrolyte and/or hydrotrope; and (iii) water.

The invention also provides a method of producing a thickened aqueous composition by diluting a concentrate as defined above.

The surfactant-containing compositions with which the invention is particularly concerned are liquid compositions intended for eventual application to a substrate to bring a surfactant into contact with that substrate, for example to cleanse it by detersive action and/or by germicidal or disinfectant action, or to condition it. Thus, the present invention is concerned with compositions containing surface active agents as active ingredients and, also, with compositions containing other principal active ingredients, e.g. disinfectants, bleaching agents or conditioning agents. Thus, for example, the composition may be cleansing compositions for application to hard surfaces such as sinks, washbasins, baths, toilet bowls, walls or floors. The invention is also concerned with compositions for application to soft surfaces such as fabrics, skin or hair, and may, thus, take the form of a shampoo, conditioner, hand soap, bubble bath, shower gel, or like product.

The concentrates employed in the invention are,by virtue of their relatively low initial viscosity, readily miscible with water whereby to more easily obtain a uniform end product.

The concentrates of the invention comprises one or more surfactants together with an electrolyte (i.e. a water-soluble compound which is ionisable in water) and/or hydrotrope and may also optionally contain one or more water-soluble or water-dispersible viscosity modifying polymeric materials to enhance the viscosity of the final diluted product. In the case of such compositions the thickening of the diluted concentrate is effected by the presence of the specified surface active agents whose thickening effect,in the concentrate, is reduced by the presence of an excess of dissolved electrolyte and/or hydrotrope. Upon dilution of the concentrate, the concentration of dissolved electrolyte and/or hydrotrope is reduced and the surface active agent component is then capable of exerting its thickening effect, possibly in combination with a viscosity modifying polymeric material as noted as above.

In accordance with a preferred embodiment of the invention, the anionic surfactant is an ether sulphate, alkylbenzene sulphonate or alcohol sulphate surfactant.

Suitable ether sulphates which may be used may be represented by the formula:

R¹ - 0 -(- CH₂-CH₂-0)_n S0₄M

in which R is an alkyl group containing from 8 to 20 carbon atoms, preferably from 10 to 14 carbon atoms; M is eg. an alkali metal, ammonium or alkylolamine cation, especially a sodium cation; and n is an integer from l to 6, preferably 1 to 3.

Suitable alkylbenzene sulphonates are those of the formula:

in which R is a ^C ₄-^C _2n' preferably C₈-C₁₂, alkyl group and M is as defined above.

Suitable alcohol sulphates are those of the formula

- SO. M

in which R and M have the meanings defined above.

Other anionic surfactants which may be used, preferably in combination with the ether sulphates, alkaryl sulphonates or alcohol sulphates, include anionic surfactants as discussed in "Surfactants Europa", 2nd Edition, G.C. Hollis Ed., Tergo Data, Darlington, England 1994. Examples of these are phosphate ester sulphosuccinates, sulphosuccinamates, α-sulpho-carboxylates and their esters, alkane sulphonates, olefine sulphonates, petroleum sulphonates, sarcosinates, taurates, isethionates, and soaps derived from natural or synthetic, saturated or unsaturated fatty acid having a ^C ₁₀-C₁₈ chain, such as sodium or potassium laurate, myristate, palmitate, oleate or stearate, or potassium or sodium soaps derived from coconut or tallow fatty acids. Particular examples of these classes of anionic surfactants include those sold under the trade names Eltesol SX30 (sodium xylene sulphonate) , Empico.1 LZ (sodium lauryl sulphate) , Triton H55 (potassium phosphate ester) , Marlinat DF8 (sodium sulphosuccinate) , Hostapur SAS 3OX (sodium alkane sulphonate) , Hostapur OS (sodium olefine sulphonate) , Petronate S (sodium petroleum sulphonate) , Hamposyl L30 (sodium lauroyl sarcosinate) , Fenopon T33 (sodium N-methyl-N-oleyl taurate) , and Fenopon AC 78 (sodium coconut isethionate) .

One particular class of nonionic surfactants for use in combination with the anionic surface active agents comprises the amine oxides of the formula:

R¹

N ^■>0

in which R is a long chain straight or branched alkyl group, typically containing 8 to 20 carbon atoms; and each of the groups R is a lower alkyl group, typically containing 1-4 carbon atoms. Particular examples of this class of nonionic surfactants are alkyl dimethyl amine oxides such as those sold under the trade names "Empigen OB" by Albright & Wilson or "Synprolam 50DMO" by ICI. Other classes of nonionic surface active agents which may be employed comprise polyalkoxylated fatty alcohols and their esters; polyalkoxylated fatty acids; polyalkoxylated alkyl phenols; alkanolamides; polyalkoxylated alkanolamides, glucosides, polyglucosides, sucrose and sugar esters, fatty esters, ethoxylated alkanolamides, ethoxylated long chain amines; alkyl amines, alkyl polyglucosides and alkyl polyglycosides. Particular examples of these classes of nonionic surfactants are those sold under the trade names Synperonic A (alcohol ethoxylates) , Crodet L24 (polyoxyethylene-24-lauric acid) , Synperonic NP (nonyl phenyl ethoxylates) , Empilan CME (coconut monoethanolamide) , Triton CG110 (alkyl glucoside) , Glucam E10 (10 mole ethoxylate of methyl glucoside) , Crodesta SL 40 (sucrose cocoate) , Empilan MAA (ethoxylated coconut monoethanolamide) , Ethomeen C12 (ethoxylated coconut amine) , and Tagosoft 16B (cetyl isooctanoate) .

Suitable amphoteric surfactants for use in combination with the anionic surfactants include alkyl betaines, alkyl aminopropionates, alkyl iminodipropionates; alkyl glycinates; carboxyglycinates; alkyl imidazolines sulphobetaines; alkyl polya inocarboxylates; polyamphocarboxyglycinates; sodium N-coco-aminopropionate, disodium N-coco-iminodiproprionate, and cocoglycinate. Particular examples of such amphoteric su.-factants are those sold under the trade names Tegobetain A4080 (alkyl dimethyl betaine) , Ampholax XCU (coco-amphoglycolate) , Amphotensid CT (alkyl imidazoline based amphoteric) , Ampholax XCO 30 (coco-amphocarboxyglycinate) and Sandobet SC (cocoamide-sulphobetaine) .

It is a matter for simple experiment to determine whether any particular surfactant or surfactant combination will or will not give the desired effect, i.e. thickening on dilution in the presence of any particular electrolyte and/or hydrotrope.

The concentration of the total surfactant component in the concentrate is up to 15% by weight; preferably up to 12% by weight, especially 2 to 10% by weight. It is generally preferred that the anionic surfactant form the major part (i.e. greater than 50% by weight) of the surfactant component, typically from 55 to 95% by weight thereof. It is an important, unexpected, advantage of the present invention, that such relatively low levels of surfactant may be employed.

With regard to the dilution factor, a dilution of from 1 to 10 times, preferably 2 to 5 times, especially about 3 times, has been found useful.

The electrolyte used in the composition will typically be sodium chloride (which is in itself a component of one important cleansing agent, sodium hypochlorite bleach) but, of course, other water-soluble electrolytes may be employed, including builders such as alkali metal carbonates, alkali metal phosphates and alkali metal silicates, alkaline builders and acids and alkalis. The amount of electrolyte required to give the desired effect is something which may be established by simple experimentation but, for example when using an ether sulphate surfactant, it has been found that concentrations, in the concentrate, of about 10% by weight or more are useful, typically giving rise to final concentrations of about 3.5% by weight or more.

Examples of suitable hydrotropes which may be used include water-soluble salts of lower alkyl (e.g. C-.-C-. alkyl) substituted aryl sulphonates such as sodium cumene sulphonate or sodium xylene sulphonate; and water-soluble alcohols such as ethanol, isopropanol and methanol.

The concentrate of the invention, on dilution with water, gives a diluted composition of the same or increased viscosity. The concentrate should be pourable and the diluted product have a perceivable viscosity, e.g. it should be apparent to the user that it has a viscosity preferably greater than that of water.

Concentrates of the invention will typically have viscosities, at 20°C, of from 10 to 3,000 cps, especially 50 to 500 cps. Diluted composition obtained by threefold dilution of such compositions will typically have viscosities; at 20°C, of from 50 to 5000 cps, especially 100 to 1000 cps (as measured with a Brookfield LV viscometer) .

By virtue of the provision of the thickening surfactant system, eventual diluted products obtained from the concentrates of the invention will often possess cleansing, detersive, softening or conditioning powers. However, the presence of other active materials in the compositions of the invention is entirely possible. One class of such other ingredients are bleaches, especially alkali metal hypochlorite bleaches. Thus, compositions in accordance with the invention may be formulated to give, upon dilution, an effective thickened bleach product and in this case the concentrate suitably contains the bleach in an amount sufficient to give from 0.1 to 10% by weight available chlorine in the diluted product. The bleach may also serve as an ancilliary component, for example in a toilet or general purpose cleaner, and in this case suitably present in an amount to give from 0.1 to 5% by weight available chlorine in the diluted product. Other bleaches such as peroxide bleaches (e.g. hydrogen peroxide) and other halogen or oxygen release bleaching agents may be employed in appropriate concentrations. Hypochlorite bleaches themselves contain electrolytes, such as sodium chloride or sodium chlorate, so that when using bleaches electrolytes present therein can provide all or a part of the desired electrolyte component of the composition; as indeed may other ingredients of the composition..

Other active ingredients which may be present include non-bleaching germicides or disinfectants and weak or strong acids which may serve as limescale removing agents e.g. glycollic acid, citric acid, hydrochloric acid, sulphamic acid, sulphuric acid, tartaric acid and maleic acid. These acids may also serve to provide some or all of the electrolyte, as indeed may comparable alkaline cleaning agents such as sodium hydroxide and sodium metasilicate. For hair or skin treatment, the composition may contain, as active ingredients, silicone surfactants, polymeric quaternary compounds, and/or protein-based surfactants. Particular example of such ingredients are Abil B9405 (polysiloxane polydimethyl dialkyl ammonium acetate copolymer) and Lameper 5 (potassium coco hydrolysed animal protein) . Surface cleaning compositions may also contain solvents such as butyl dioxitol aliphatic hydrocarbons, pine oil, alpha-terpineol, d-limonene, orange terpene, ethylene glycol mono-n-butyl ether, diethyl carbonate, morpholine, hexylene glycol and propylene carbonate. In general, any solvent employed should, at 25°C (a) have a molar volume below about 200 cc/g.mol; (b) a polarity parameter of 0 to about 3 (Cal/cc)¹ , and (c) a hydrogen bonding parameter of about 6 (Cal/cc)¹'².

In some cases the solvent may act as the hydrotrope in all or in part.

In addition to active ingredients, compositions in accordance with the invention may also contain colouring agents, such as dyestuffs, fragrances, or sequestrants. In this connection it may be noted that commercially available fragrances may in themselves have a viscosity-modifying effect.

It has further been found that the addition of water-soluble or water-dispersible viscosity-modifying polymeric materials can serve to provide a final diluted product of enhanced viscosity.

A wide variety of organic polymers are suitable for use in accordance with the invention. Such polymers may be wholly synthetic or may be semi-synthetic polymers derived from natural materials. Thus, for example, on class of polymers for use in accordance with the invention are chemically modified celluloses such as ethyl cellulose, methyl cellulose, sodium carboxymethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, ethyl hydroxyethyl cellulose, carboxymethyl hydroxyethyl cellulose, and hydroxyethyl cellulose. Wholly synthetic polymers which may be used in accordance with the invention include polyvinyl alcohols; water-soluble partially hydrolysed polyvinyl acetates; polyacrylonitriles; polyvinyl pyrrolidones; water-soluble polymers of ethylenically unsaturated carboxylic acids, such as acrylic acid and methacrylic acid, and salts thereof; base-hydrolysed starch-polyacrylonitrile copolymers; polyacrylamides; polyether resins; and carboxypolymethylenes.

The polymeric materials may suitably be added in amounts of up to 10% of the composition, generally up to 5% thereof.

In accordance with one preferred feature of the invention, concentrates in accordance with the invention are put up in sealed containers containing a unit dose of the concentrate. These have the advantage of ease of use, recyclability, reduced packaging and ease of obtaining the appropriate dilution.

The term "unit dose", as used herein, is intended to refer to a predetermined volume of concentrate intended to be diluted with a predetermined volume of water, whereby to provide a predetermined volume of diluted liquid composition of similar or increased viscosity. The dilution may be effected by adding water to concentrate or vice versa and, where desirable, may be effected stepwise. Thus, the unit doses of the invention are "one-shot" doses, to be wholly used in one overall dilution operation.

The sealed container, containing the concentrate, may take any of a wide variety of forms and thus, for example, may be a glass, metal or plastics container with a sealed screw or other eventually releasable cap such as a bung or cork; or a sachet. In use, the whole contents of the sealed container are diluted with water. This may be achieved for example by placing the contents of the container in a dilution vessel and diluting with an appropriate quantity of water or vice versa, i.e. adding to the contents of the container to water in a dilution vessel. To assist the user, such a dilution vessel conveniently takes the for... of a glass or plastics container provided with a releasable cap (e.g. a screw cap, cork or bung) and having the appropriate volume for dilution of a predetermined quantity of concentrate as contained in the sealed container.

In use, the contents of a sealed container are placed in the dilution vessel and then diluted with water (generally to fill or make up to an appropriately recommended level on the dilution container) . The dilution container is then sealed and shaken to thoroughly mix concentrate and water, thereby to provide the user with an appropriate quantity of suitably thickened composition. As will be appreciated, the sealed containers of the invention are particularly suitable for domestic or like use, making it possible for the purchaser to obtain suitable quantities of thickened composition whilst only purchasing relative small lots of concentrate. The concentrate also lends itself to transportation, in that no unnecessary water is required, and to industrial use.

Suitably, for domestic use, a sealed container in accordance with the invention will contain, as unit dose of liquid concentrate, from 5 to 5000ml thereof, preferably 25 to 5000ml thereof, especially 50 to 1250ml thereof. Typical specific volumes of unit dose of concentrate are 125, 250, 500ml. Such specific unit doses may, for example, be used to make up total volumes of thickened diluted concentrates of 500, 1000, 2000ml, respectively.

For industrial use, the sealed container may, for example, take the form of a can, drum or tanker for later dilution with water in a single overall operation in appropriate apparatus. In order that the invention may be well understood the following Examples of concentrates in accordance with the invention are given by way of illustration only. In the Examples all figures in the Tables (other than viscosity figures) are parts by weight. All viscosities are measured at 20°C using a Brookfield LV viscometer.

Examples 1-5 (Bleaches]

Sodium hypochlorite 9.5 9.5 9.5 9.5 9.5 Sodium lauryl ether sulphate 2 mole 4.86 1.89 2.16 5.13 3.51 Myristyl dimethyl amine oxide 0.75 3.5 3.25

Lauryl dimethyl amine oxide 0.75 2.0

Soft water to 100 to 100 to 100 to 100 to 100

Viscosity cone, cps 124 49 67 101 88 Viscosity 1:2 dilution, cps 338 >500 >500 340 475 Examples 6-9 (Bleaches) 6 7 8

Sodium hypochlorite 9.5 9.5 9.5 9.5

Sodium lauryl ether sulphate 2 mole 4.32 2.70

Sodium lauryl ether sulphate 3 mole 4.59 3.78

Lauryl dimethyl amine oxide 1.25 2.75 1.0 1.75

Soft water to 100 to 100 to 100 to 100

Viscosity cone, cps 211 115 110 38 Viscosity 1:2 dilution, cps 422 432 192 317

Exam les Q - 13

10 11 12 13

Sodium lauryl ether sulphate 2 mole 9.45 5.40 6.75

Myristyl dimethyl amine oxide 1.25 1.25 1.25 5.00

Electrolyte** 18.0 18.0 18.0 18.0

Soft water to 100 to 100 to 100 to 100

Viscosity cone, cps 402 144 252 2020 Viscosity 1:2 dilution, cps 3470 190 352 3310

** 13:5 mixture of NaCl: MgS0₄.7H₂0 Examples 14 - 16 14 15 16

Sodium lauryl ether sulphate 2 mole 1.4 2.7 4.1

Alkyl amido betaine 1.5 1.5 1.5

Electroyte** 18.0 18.0 18.0

Soft water to 100 to 100 to 100

Viscosity cone, cps 63 46 67 Viscosity 1:2 dilution, cps 189 284 952

Examples 17 - 19 17 18 19

Sodium lauryl ether sulphate 2 mole 6. .80 8.10 9.50

Alkyl amido betaine 1. .5 1.5 1.5

Electroyte** 18. .0 18.0 18.0

Soft water to 100 to 100 to 100

Viscosity cone, cps 136 174 272 Viscosity 1:2 dilution, cps >5000 >5000 >5000

** 13:5 mixture of NaCl: gS0₄.7H₂0, Exam les 20 and 21

20 21

Sodium lauryl ether sulphate 2 mole 6.8 9.5

Cocoamphocarboxyglycinate 1.5 1.5

Electrolyte** 18.0 18.0

Soft water to 100 to 1

Viscosity cone, cps 163 290

Viscosity 1:2 dilution, cps 604 1413

** 13:5 mixture of NaCl: MgS0₄.7H₂0

Examples 22 and 23 22 23

Sodium salt of polymeric carboxylate 0 2.0

Sodium lauryl ether sulphate 2 mole 8.75 8.75

Sodium chloride 19 19

Soft water to 100 to 100

Viscosity cone, cps 452 107

Viscosity 1:2 dilution, cps 712 685

Supplied as Dispex N40 ex Allied Colloids. EXAMPLES 24 - 31

The compositions listed in the following Table were made up, each containing, in addition to the specified ingredients in soft water to a total of 100% by weight.

Viscosity (Cps)

Example Surfactants Electrolyte Concentrate Dilution (% by wt) {% by wt)

24 sodium NaCl- 113 (1:1) alkyl- 3.0% h JJPCTl1i7iuPCTXlPC sulphonates (Nansa SS60) 14.5%

25 II NaCl- 50(1:1) 6%

26 Triethanol- NaCl- 71 245(1:1) amine alkyl 5% benzene sulphonate (Nansa TS 50/F) - 14.5%

27 II NaCl- 77 230 (1:1) 6%

28 Ammonium NaCl- 1125 3165(1:1) alkyl 7.5% sulphate (Empicol AL 25EP) 14.5%

29 II _ _ NaCl- 32 980 (1:2) 10.0%

30 Sodium Triammonium 700 6100 (1:1) lauryl citrate - ether 18% sulphate

10%

31 II Sodium 2100 4200 formate-

15%

Claims

CLAIMS :

1. An aqueous, surfactant-containing, concentrate which on dilution with water gives a diluted liquid of the same or increased viscosity, the composition comprising: -

(a) up to 15% by weight of a surfactant component consisting of one or more anionic surfactant alone or in combination with one or more nonionic or amphoteric surfactants;

(b) an electrolyte and/or hydrotrope; and

(c) water.

2. A concentrate as claimed in claim 1 also containing 0.1 to 10% by weight of a water-soluble or water-dispersible polymeric viscosity-modifying material