DUAL COMPARTMENT CONTAINER COMPRISING FRAGRANCE AND FABRIC-SOFTENING COMPOSITION
The present invention relates to a container for a fabric softening composition.
Fabric softening compositions are well known. Typically, these compositions are introduced during the rinse cycle of a washing machine to soften and remove static from fabrics. An important feature of fabric softening compositions is that the fragrances included in the fabric softening compo¬ sition are deposited onto the fabric during the rinse cycle.
It has been found that the performance and the stabil ity of the fragrance may depend on its interaction with other in- gredients in the fabric softening composition. Moreover, as the fragrance can contain different components with differ¬ ent rates of evaporation, the perception of the fragrance can change with time. In certain cases, this can lead to the loss of the characteristic aroma of the fragrance.
Several Patents describe a method of encapsulating an hydro¬ phobic core material into a polymeric shell material which produces capsules of the required size, friability ancL water insolubility. The microcapsule shell wall can be composed of a wide variety of polymeric materials including polyure- thane, polyolephin, polyamide, polyester, polysaccharide, silicon resin or epoxy resins.
Microcapsules having an hydrophobic core and a polymerr shell can be prepared by any conventional process. Generally, such method as coacervation and interfacial polymerisation can be employed in well know manner to produce microcapsules
of the desired characteristic. Such methods are described in US 3,870,542 or US 3,041,288. US 6,106,875 describes a method of encapsulating a fragrance compound into a micro¬ capsule having a hydrogel shell and an oil core.
Encapsulation may help to protect the fragrance from evapo¬ ration, chemical reactions and physical interactions until needed. Thus, by including such microencapsulated fra¬ grances in fabric-softening compositions, loss of fragrance perception due to evaporation may be reduced.
However, we have found that the fabric composition does not provide an ideal environment for encapsulated fragrance. The compositions are typically lipophilic. Therefore, the fragrances, which are also typically lipophilic, leach out of the capsule into the composition over a period of time, from days up to weeks.
According to the present invention, there is provided a con- tainer comprising a first compartment containing a fragrance, and a second compartment containing a fabric softening com¬ position.
By separating the fragrance from the fabric-softening compo¬ sition in this manner, any negative interactions between the fragrance and the fabric softening composition are minimised or eliminated.
The present invention will now be further described. In the following passages, different aspects of the invention are defined in more detail. Each aspect so defined may be com-
bined with any other aspect or aspects unless clearly indi¬ cated to the contrary. In particular, any feature clearly indicated as being preferred or advantageous may be combined with any other feature or features indicated as being pre- ferred or advantageous.
Preferably, the fragrance is an encapsulated fragrance. For example, the fragrance may be encapsulated in a microcapsule having a polymeric shell material surrounding a lipophilic core. When such an encapsulated fragrance is included in a conventional fabric softening composition, the fragrance has a tendency to leach out of the microcapsule due to interac¬ tions between the lipophilic fabric softening composition and the lipophilic core of the microcapsule.
Preferably, the fragrance is contained in the first compart¬ ment together with a liquid carrier, ideally the liquid car¬ rier is hydrophilic or is aqueous. Thus, the fragrance may be dissolved or dispersed in the liquid carrier to produce a liquid solution, dispersion or emulsion. The resulting liq¬ uid may contain from 0.1 to 5.0 weight %, preferably, 0.2 to 3 weight %, for example, 0.3 to 1 weight % of fragrance.
Any suitable liquid carrier may be employed. In one embodi- ment, a mixture of two or more liquid carriers is employed. Preferably, the liquid carrier contains or consists essen¬ tially of water. For example, the first compartment of the container of the present invention may contain an aqueous solution, wherein the fragrance is preferably in an encapsu- lated form.
The first compartment may also contain a suspending agent, especially where the fragrance is emulsified or, when encap¬ sulated, dispersed in the first compartment. Ideal suspend¬ ing agents are viscosifying agents (such as thickening agents) , liquid structurants (such as gelling agents) and dispersants (such as charged polymers) . Some compounds may act by all three mechanisms, such as anionically or cationi- cally charged gums, such as guar, xathan or cellulose de¬ rivatives (dextrins) . For the purposes hereinafter we have simply reffered to a suitable agent as a thickener.
The thickener is present in the composition in amounts of from 0.01% to 5%, preferably from 0.03% to 3%, and even more preferably from 0.05% to 1%, by weight. Preferably the thickener is substantive to the fibre of the fabric being treated, this means that the thickener associates with the fibre of the fabric treated, remaining, at least in part, on the fibre after rinsing and drying. It will be appreciated that the thickener selected will not necessarily be substan- tive to all possible types of fabric fibre, especially syn¬ thetic fibre. It is preferred that the thickener selected is one that is substantive to natural fibres, especially cotton or wool .
It will be appreciated that the thickener may also act as capsule transfer agent, as described below, especially when it is cationic.
Examples of suitable thickeners are water-soluble polymers.
By water-soluble we mean that the thickener is found in the majority, greater than 90%, in the water phase rather than the oil phase of the composition.
Suitable polymers are polyacrylates, co-polymers of poly- acrylates and polysaccharides .
Suitable polysaccharides are high molecular weight materials whose mass-average molecular weight (determined, for in- stance, by light scattering) is generally from 2,000 to 5,000,000, preferably from 5,000 to 3,000,000, more prefera¬ bly from 100,000 to 1,000,000. The polysaccharide used is preferably a polygalactomannan (a polygalctomannan being a carbohydrate which is predominantly comprised of mannose and galactose units) . Preferred polysaccharides are selected from; chitin and gum (including but not limited to; xanthan, locust bean, guar, honey locust and flame tree, preferably guar gum is used) .
Guar gums are polygalactomannans and are defined in the Haw- ley's Condensed Chemical Dictionary, 12th Edition, published by Von Nostrand Reinhold in 1993, and edited by E J Lewis, and these pages are incorporated herein by reference.
Preferred chemical modification of the carbohydrate is es- terification or etherification on the free hydroxyl groups of the carbohydrate.
Preferred derivatives are those, which includes hydrolysed forms, modified with a nonionic substituent, such as hy- droxylCl-6alkyl, an anionic substituent, such as car- boxyCl-δalkyl, or a cationic substituent, such as a primary
amino, secondary amino, tertiary amino, quartenary ammonium, sulfonium or phosphonium group.
Cationically modified polymers are preferred. Quaternary am- monium derivatives of carbohydrates, especially of chitins and guar gums, are of particular interest, such as, quater¬ nary ammonium guar gums. A preferred derivative includes those modified with a cationic group, which additionally may also be modified with a nonionic group first. A preferred cationic group is quartenary ammonium, ideally selected from one of the following;
[N(Rl) (R2) (R3) (R4) ] +X'
wherein Rl is a monohydroxylated or polyhydroxylated Cl- δalkyl; R2 and R3 are independently, Cl-βalkyl; R4 is a Cl- 24alkyl group; and X" is a counterion, as defined above.
Methods of making such polysaccharides derivatives are de- scribed in WO9818828 and the specific examples 1 to 29 are each incorporated herein by reference.
Representative classes include quaternary ammonium group- containing glycogen, gum or chitin polysaccharides.
In addition we have found that xanthan gum can form a thick¬ ened stable solution which is stable and perform well. Xan¬ than gum is produced by bacteria fermentation and was the first polysaccharide produced on large scale using X.campestris. Such a technique offers the advantage of re¬ producible physical and chemical properties, with a stable cost / supply. Unlike other microbial extracellular poly-
saccharide, the composition of the polymer varies with Xan- thomonas strain and culture conditions and in the presence or absence of pyruvate and/or acetate substituents.
The polysaccharide forms highly viscous solution at low polymer concentration, which are atypically insensitive to a wide range of salt concentration, pH and temperature. In addition to this, Xanthan solutions exhibit stronger shear thinning behaviour showing non-Newtonian behaviour, a meas- urable yield stress from about 1% polymer concentration, emulsion stabilising and particle suspending abilities, which are all indicative of intermolecular associations.
This natural polysaccharide is widely used in the food in- dustry and to lesser extent the pharmaceutical industry. Most of the commercial Xanthan contain a variable amount if Na+ , K+, Ca2+ salts, and approximately 30-40% pyruvate con¬ tent with 60-70% acetate content (although this is subject to "variability)
Preferably, but not required, the first compartment may op¬ tionally also include a surface active agent such as non ionic surfactant. Acceptable non-limiting non-ionic surfac¬ tant may or can be from any of the following non-ionic types: alcohol ethoxylates, alkyl phenol ethoxylates, fatty acid ethoxylates, fatty amine ethoxylates, polypropylene gly¬ col ethoxylate, alkyl polyglucosides, amine oxide alkanola- mid.es and mixture thereof and the like.
Encapsulated Fragrance
Preferably the fragrance is encapsulated. Or only part of the fragrance is encapsulated. Up to an amount of 3% by weight of ttie first composition can be an encapsulated fra¬ grance.
The microcapsule shell wall can be composed of a variety of polymeric materials including polyurethane, polyolefin, polyamide, polyester, polysaccharide, silicone resins and epoxy resins . Many of these types of polymeric microcapsule shell materials are further described and exemplified in Ida et al; U.S. Pat. No. 3,870,542; issued Mar. 11, 1975.
Highly preferred materials for the microcapsule shell wall are the aminoplast polymers comprising the reactive products of urea and aldehyde, e.g. formaldehyde. Such materials are those which are capable of acid condition polymerization from a water*-soluble prepolymer state. Such prepolymers are made by reacting urea and formaldehyde in a formalde¬ hyde:urea molar ratio of from about 1.2:1 to 2.6:1. Thio- urea, cyanurramide, guanidine, N-alkyl ureas, phenols, sul¬ fonamides, anilines and amines can be included in small amounts as -modifiers for the urea. Polymers formed from such prepolymer materials under acid conditions are water- insoluble and can provide the requisite capsule friability characteristics as described more fully hereinafter.
Microcapsules having the liquid cores and polymer shell walls as described above can be prepared by any conventional process which produces capsules of the requisite size, fri- ability and water- insolubility. Generally, such methods as coacervation. and interfacial polymerisation can be employed in known manner to produce microcapsules of the desired
characteristics. Such -methods are described in Ida et al; U.S. Pat. No. 3,870,542; issued Mar. 11, 1975; Powell et al; U.S. Pat. No. 3,415,758; issued Dec. 10, 1968 and Anthony; U.S. Pat. No. 3,041,288; issued June 26, 1962. All of these patents are incorporated herein by reference.
Microcapsules made from the preferred urea-formaldehyde shell materials can be made by an interfacial polymerisation process described more fully in Matson; U.S. Pat. No. 3,516,941. By that process an aqueous solution of a urea- formaldehyde precondensate (methylol urea) is formed con¬ taining from about 3% to 30% by weight of the precondensate. Lipophilic water-insoluble liquid core material (e.g., fra¬ grance) is dispersed throughout this solution in the form of microscopically-sized discrete droplets. While maintaining solution temperature between 20°C and 90°C, acid is then added to catalyse polymerisation of the dissolved urea- aldehyde precondensate. If the solution is rapidly agitated during this polymerisation step, shells of water-insoluble, urea-formaldehyde polymer form around and encapsulate the dispersed droplets of liquid core material.
Ideally the microcapsules vary in size between 5 microns and 500 microns, preferably between about 10 microns and 100 mi- crons. Preferably the capsules used in the present inven¬ tion have an average slxell thickness ranging from about 0.1 to 50 microns, preferably from about 0.4 to 4 microns.
The microcapsules should also be friable in nature. Fri- ability refers to the ability of the microcapsules to rup¬ ture or break open when subjected to direct external pres¬ sures or shear forces. For purposes of the present inven-
tion, the microcapsules utilised aire "friable" if, while at¬ tached to fabrics treated therewith., they can be ruptured by the forces encountered when the capsule- containing fabrics are tumbled in an automatic laundry dryer or are manipulated by being worn or handled. Microcapsules made with the above described shell materials will be "friable" if they fall within the essential capsule size and shell thickness limi¬ tations provided above.
The fragrance may be encapsulated ULsing any suitable method.
Highly preferred material for the microcapsule shell wall are the aminoplast polymers comprising the reactive products of urea and aldehyde, e.g. formaldehyde and or melamine and aldehyde.
Microcapsules having a lipophilic core and a polymer shell can be prepared by any conventional process which produce capsules of the requisite size, fr±ability and water insolu- bility. Generally, such method as coacervation and interfa- cial polymerisation.
In one embodiment, a microcapsule having a hydrogel shell and an oil core is prepared, for example, in dry form. A fragrance is then transported thrrough the hydrogel shell, whilst the oil core is retained within the microcapsule.
The fragrance may be transported through the hydrogel shell by diffusion. This diffusion step may be carried out in the presence of a solvent such as wate-tr. In one embodiment, the fragrance is provided in a gaseous or liquid state and transported across the hydrogel shell by aqueous diffusion.
The shell may consist of a carbohydrate or a protein, which may be crosslinked or non-crosslinked, or a synthetic poly¬ mer such as polyvinyl pyrollidone or methyl cellulose. The oil core may comprise, for example, vegetable oil, mineral oil, benzyl alcohol or mixtures thereof. In a. preferred em¬ bodiment, the oil is a short chain triglyceride of fraction¬ ated coconut oil. As more particularly defined hereinafter, "oil" is meant to include a wide range of substances that are dispersible in water due to their hydrophobic nature.
Suitable methods for microencapsulating the fragrance are described in US 6,106,875 and US 6,607,771.
Capsule Transfer Agent
To aid deposition of the capsule onto the fabric a capsule transfer agent is preferably added to the composition, which may be present in either composition. Preferred amounts of capsule transfer agents are >1, 4, 6, 8, 10, 12% by weight. Ideal amounts are <30, 25, 20, or 15 % by weight.
Attachment of the above-described microcapsules to the fab¬ rics being treated therewith is facilitated by surrounding the microcapsules with a particular type of capsule transfer agent. Capsule transfer agents employed in the present in¬ vention are those substantially water- insoLuble materials which are fabric substantive and which have a. melting point with the range of from about 40°C to 15O°C, preferably within the range of from about 49°C to 105°C. By "substan¬ tially water-insoluble" herein is meant a water insolubility of 1% by weight, or less, at 3O0C.
Especially suitable capsule transfer agents are those cat i- onic and nonionic organic materials which are generally em¬ ployed as conventional fabric softening agents during the washing, rinsing or drying cycles of the household laund.ry process. Materials of this type generally have the requi¬ site fabric substantivity for use herein.
Suitable cationic capsule transfer agents include any of the cationic compounds. Used as fabric conditioning actives, such as described in the second composition.
Nonionic capsule transfer agents include a wide variety of materials including sorbitan esters, fatty alcohols and their derivatives, diamine compounds and the like. One prre- ferred type of nonionic capsule transfer agent comprises the esterified cyclic dehydration products of sorbitol, i.e., sorbitan ester. Sorbitol, itself prepared by catalytic hry- drogenation of glucose, can be dehydrated in well-known fashion to form mixtures of cyclic 1,4- and 1,5-sorbitol an¬ hydrides and small amounts of isosorbides. (See Brown; U.S. Pat. No. 2, 322,821; issued June 29, 1943) The resulting complex mixtures of cyclic anhydrides of sorbitol are col¬ lectively referred to herein as "sorbitan". It will be rec- ognized that this "sorbitan" mixture will also contain some free uncyclized sorbitol.
Sorbitan ester capsule transfer agents useful herein are prepared by esterifying the "sorbitan" mixture with a fatty acyl group in standard fashion, e.g., by reaction with, a fatty (C10-C24) acid or fatty acid halide. The esterifioa- tion reaction can occur at any of the available hydroεyl
groups, and various mono-, di-, etc., esters can be pre¬ pared. In fact, complex mixtures of mono-, di-, tri, and tetra- esters almost always result from such reactions, and the stoichiometric ratios of the reactants can simply be ad- justed to favor the desired reaction product. The sorbitan mono-esters and di-esters are preferred for use as the cap¬ sule transfer agent in the present invention, but all such esters are useful .
The foregoing complex mixtures of esterified cyclic dehydra¬ tion products of sorbitol (and small amounts of esterified sorbitol) are collectively referred to herein as "sorbitan esters". Sorbitan mono- and di-esters of lauric, myristic, palmitic, stearic and behenic acids are particularly useful herein for facilitating transfer of the microcapsules to fabrics being treated. Mixed sorbitan esters, e.g., mix¬ tures of the foregoing esters, and mixtures prepared by es- terifying sorbitan with fatty acid mixtures such as the mixed tallow and hydrogenated palm oil fatty acids, are use- ful herein and are economically attractive. Unsaturated ClO -C18 sorbitan esters, e.g., sorbitan mono-oleate, usually are present in such mixtures. It is to be recognized that all sorbitan esters, and mixtures thereof, which are essen¬ tially water-insoluble and which have fatty hydrocarbyl "tails", are useful capsule transfer agents in the context of the present invention.
The preferred alkyl sorbitan ester capsule transfer agents herein comprise sorbitan monolaurate, sorbitan mono- myristate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monobehenate, sorbitan dilaurate, sorbitan di- myristate, sorbitan dipalmitate, sorbitan distearate, sorbi-
tan dibehenate, and mixtures thereof, the mixed coconutalkyl sorbitan mono- and di-esters and the mixed tallowalkyl sor- bitan mono- and di-esters. The tri- and tetra-esters of sorbitan with lauric, myristic, palmitic, stearic and be- henic acids, and mixtures thereof, are also preferred herein.
Sorbitan esters of the foregoing type are more fully de¬ scribed and exemplified in the copending application of Wa- hib N. Zaki; Ser. No. 543,607; filed Jan. 23, 1975. This application is incorporated herein by reference.
Another useful type of nonionic capsule transfer agent en¬ compasses the substantially water-insoluble compounds chemi- cally classified as fatty alcohols. Mono-ols, di-ols and poly-ols having the requisite melting points and water- insolubility properties set forth above are useful herein. Such alcohol-type capsule transfer materials also include the mono- and di-fatty glycerides which contain at least one "free" OH group.
All manner of water-insoluble, high melting alcohols (in¬ cluding mono and di-glycerides) , are useful herein, inasmuch as all such materials are fabric substantive and tend to fa- cilitate attachment of the microcapsules herein to fabric surfaces. Of course, it is desirable to use those materials which are colorless, so as not to alter the color of the fabrics being treated. Toxicologically acceptable materials which are safe for use in contact with skin should be cho- sen.
A preferred type of unesterified alcohol useful herein in¬ cludes the higher melting members of the so-called fatty al¬ cohol class. Although once limited to alcohols obtained from natural fats and oils, the term "fatty alcohols" has come to mean those alcohols which correspond to the alcohols obtainable from fats and oils, and all such alcohols can be made by synthetic processes. Fatty alcohols prepared by the mild oxidation of petroleum products are useful herein.
Another type of material which can be classified as an alco¬ hol and which can be employed as the capsule transfer agent in the instant invention encompasses various esters of poly- hydric alcohols. Such "ester- alcohol" materials which have a melting point within the range recited herein and which are substantially water-insoluble can be employed herein when they contain at least one free hydroxyl group, i.e., when they can be classified chemically as alcohols.
The alcoholic di-esters of glycerol useful herein include both the 1, 3-di-glycerides and the 1,2-di-glycerides. In particular, di- glycerides containing C8-C20, preferably C10-C18, alkyl groups in the molecule are useful capsule transfer agents.
Non-limiting examples of ester-alcohols useful herein in¬ clude: glycerol-1,2-dilaurate; glycerol-1, 3-dilaurate; glyc¬ erol-1,2-myristate; glycerol-1,3-dimyristate; glycerol-1,2- dipalmitate; glycerol-1, 3- dipalmitate; glycerol-1,2- distearate and glycerol-1, 3-distearate. Mixed glycerides available from mixed tallowalkyl fatty acids, i.e., 1,2- di- tallowalkyl glycerol and 1, 3-ditallowalkyl glycerol, are economically attractive for use herein. The foregoing es-
ter-alcohols are preferred for use herein due to their ready availability from natural fats and oils.
Mono- and di-ether alcohols, especially the C10-C18 di- ether alcohols with at least one free -OH group, also fall within the definition of alcohols useful as capsule transfer agents herein. The ether-alcohols can be prepared by the
Williamson ether synthesis. As with the ester-alcohols, the reaction conditions are chosen such that at least one free, unetherified -OH group remains in the molecule.
Ether-alcohols useful herein include glycerol-1,2-dilauryl ether; glycerol-1,3-distearyl ether; and butane tetra-ol- 1, 2, 3-trioctanyl ether.
Yet another type of nonionic capsule transfer agent useful herein encompasses the substantially water-insoluble diamine compounds and diamine derivatives. The diamine capsule transfer agents are selected from the group consisting of particular alkylated and acylated diamine compounds.
Fragrance
Any suitable fragrance may be employed in the present inven- tion. Preferably, the fragrance comprises at least one aroma chemical having a clogP of 3 or less. The aroma chemical may have a vapour pressure at 250C of greater than 0.07m mm Hg, more preferably greater than 0.7 mm Hg, for ex¬ ample 0.9 to 1.2 mm Hg. Vapour pressure and clog may be de- termined using ACD software from Advanced Chemicals Develop¬ ment ACD/Labs Software (Toronto, Ontario Canada) .
Examples of suitable aroma chemicals include phenyl ethyl alcohol, phenyl ethyl formate, FRUCTONE (ethyl 2-methyl-1, 3- dioxide-2-acetate) , methyl phenyl acetate, methyl amyl ke¬ tone, methyl hexyl ketone, ethyl phenyl acetate, CYCLAL (2,4-dimethyltetrahydeobenzaldehyde) , cis-3-hexanyl formate, carvone, methyl phenyl acetate, prenyl acetate, isobutyl acetate, para cresyl acetate, cyclohexyl acetate, para tolyl aldehyde, cis-3-hexenol, aldehyde C7, aldehyde C8, ethyl caproate, ethyl-2-methyl-butyrate, ethyl butyrate, phenyl acetaldehyde, MANZANATE (ethyl 2-methylpentanoate) , aceto- phenone, alcohol C6, amyl acetate, amyl alcohol, ANAPEAR
(4, 7-octadienoic acid, methyl ester) , benzaldehyde, benzyl acetate, butyl acetate, butyl butyrate, cyclohexyl acetate, diethyl malonate, ethyl amyl ketone, ethyl benzoate, euca- lyptol, alpha fenchone, fenchyl alcohol, hexyl acetate, iso pulegol, linalool oxide, melonal, nerol oxide, nonadienal, preonil, safranal and trans-hexenal .
Suitable fragrances are described in further detail in WO 03/016451.
Fabric softening active
The fabric-softening composition may include any suitable fabric-softening active. The fabric-softening active may be present in the fabric softening composition in an amount of 1% to 30% by weight, preferably from 2% to 20% by weight, and more preferably from 2% to 18% by weight of the fabric softening composition.
Preferably, a cationic active is employed as the fabric- softening active. Suitable cationic actives include dial-
kiyldimethyl ammonium chloride, dialkyldimethyl ammonium methyl sulfate, di (hydrogenerated tallow) dimethyl ammonium chloride, dihexadecyldiethylammonium chloride, distearyldi- methylammonium chloride, dibehenyldimethylammonium chloride, όli (coconut alkyl) dimethyl ammonium chloride, ditallowimethyl ammonium chloride, ester quaternium compounds, dialkylyloxy dimethyl ammonium chloride, N,N-di (tallowyl-oxy- ethyl) -N N- cLimethylammonium chloride, N,N- (ditallowoxyl-oxy-ethyl) -N,N- cLimethyl ammonium chloride, dialkyl imidazolium methyl sul- fate, amido silicones, cetyl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, and mixtures thereof (see WO 03/016451) .
Preferably, the cationic active is a compound of formula of formula (I) :
(I)
wherein Q is selected from -CH2-, -O-C(O)-, -C-(O)-O- and -0-C(O)-O- (preferably -CH2-) ;
R1, R2 and R3 are independently selected from Ci-C4 alkyl or
Ci-C4 hydroxyalkyl or H (preferably Cx-C4 alkyl, ideally methyl or ethyl) ;
T1 is C6-C22 alkyl or alkenyl (preferably alkyl) ; n is an integer from 0 to 4 (preferably n is 2) ; and
X" is a softener-compatible anion.
The anion ±s merely present as a counterion of the posi¬ tively charged quaternary ammonium compounds. The nature of the counter±on is not critical. However, non-limiting exam¬ ples of softener-compatible anions include chloride or methyl sulfate. Preferably chloride is employed.
The alkyl OJC alkenyl chain Tl should contain at least 5 car¬ bon atoms, preferably at least 13 carbon atoms, more pref¬ erably at least 15 carbon atoms. The chain may be straight or branched .
A specific example of a quaternary ammonium compound suit¬ able for use in the aqueous fabric softening compositions herein is h/ydrogenated tallow trimethyl ammonium chloride.
The fabric softening composition may also comprise a liquid carrier. The liquid carrier may form at least 20%, more preferably at least 30% by weight of the fabric softening composition .
Suitable liquid carriers are selected from water, organic solvents and mixtures thereof. Suitable organic solvents include low molecular weight organic solvents having molecu¬ lar weights of less than 200. Examples of suitable low mo- lecular weight organic solvents include monohydric alcohols, such as etϊianol, propanol, iso-propanol and butanol; dihy- dric alcohols, such as glycol; trihydric alcohols, such as glycerol, and polyhydric (polyol) alcohols.
Preferably, the carrier is water or a water-containing mix¬ ture. Where a water-containing mixture is employed as a
carrier, water preferably forms at least 80 %, more prefera¬ bly at least 90 % by^ weight of the carrier. In one embodi¬ ment, a mixture of water and a low molecular weight organic solvent having a molecular weight of less than 200 is em- ployed. Examples of suitable low molecular weight organic solvents include monohydric alcohols, such as ethanol, pro- panol, iso-propanol and butanol; dihydric alcohols, such as glycol; trihydric alcohols, such as glycerol, and polyhydric (polyol) alcohols.
The fabric softening composition may further comprise a fab¬ ric co-softener. Fabric co-softeners are preferably non- quaternary hydrophilic compounds that are added to boost softening performance. Preferred levels are from 0.1 to 10% by weight or 0.2 to 5% by weight of the fabric softening composition.
The co-softener may be an amine, a silicone, a film-forming rinse agent, amine oxides, betaines and alkali metal soaps. The preferred fatty acid precursors of the alkali metal soaps contain a high, proportion of unsaturation, with oleyl groups being the most preferred. Mixtures of co-softeners may be employed.
Among the suitable co-softeners are amines of formula (II) below:
NR3R4R5
At least one of R3, R4 and R5 is a Ci6.22 alkyl or alkenyl (preferably alkenyl) , whilst the remaining groups, if any, are Ci-4 hydroxyalkyl or hydrogen. Preferably at least one of R3, R4 and R5 is a C17-I9 alkyl or alkenyl (preferably al¬ kenyl) and more preferably a Ci8 alkyl or alkenyl (preferably alkenyl) The remaining group (s) , if any, are preferably hydroxyethyl . In one embodiment, one or two of R3, R4 and R5 is a C16-22 alkyl or alkenyl (preferably alkenyl) , whilst the remaining group is Ci_4 hydroxyalkyl or hydrogen.
The co-softener may be a silicone oil. Silicone oils are effective at lubricating and smoothing fibers. This allows fibers to slip or glide past each other.
Preferably, the silicone oil is based on a dimethylsiloxane silicone, more preferably a volatile dimethylsiloxane.
Non-limiting examples of usefiαl silicones in the composi¬ tions of the present invention include non-curable silicones such as volatile silicones and polydimethylsilicone, and curable silicones such as am±nosilicones, phenylsilicones and hydroxysi1icones.
Preferred silicones are those of formula (III) below
(Rl)aG3-a-Si- (-O-SiG2)n- (OSiGb(Rl) 2_b)m-O-Si-G3-a(Rl) a
wherein G is selected from the group consisting of hydrogen, phenyl, OH, and/or C1-C8 alkyl; a denotes 0 or an integer from 1 to 3 ; b denotes 0 or 1; the sum of n + m is a number from 1 to 2,000; Rl is a monovalent radical of formula
CpH2+pL in which p is an integer from 2 to 8 and L is se¬ lected from the group consisting of :
-N(R2) CH2-CH2-N(R2)2; -N(R2)2 ; -N+ (R2) 3A_~; and -N+(R2)CH2- CH2N+H2A"
wherein each R2 is chosen from the group consisting of hy¬ drogen, phenyl, benzyl, saturated hydrocarbon radical, and each A"denotes a compatible anion, e.g. a halide ion.
When silicone oils are included in the falbric softening com¬ position, surfactants may need to be used to emulsify the silicone oils. Although surfactant (typically cationic or non-ionic) is important for stabilising the silicone emul- sion, it is preferred to use the lowest Hevel of surfactant possible. Preferred methods of emulsifying suitable sili¬ cone oils are disclosed in WO 01/07710 or US2003143176.
A film-forming rinse agent may also be used as the co- softener. The film forming rinse agent nay be deposited on the fabric to form a film network over the fabric. Examples of suitable film-forming rinse agents include polyurethanes. Suitable polyurethanes include those comprising the struc¬ tural units :
- (0-OC-NH-R-NH-CO-O-R' )n
wherein n is from 100 to 10,000 and R and R' are each a hy¬ drogen or a hydrocarbyl group.
The pH of the fabric softening composition may be 2 to 5. pH is measured in the neat compositions at 20°C. pH-
regulating agents may be employed to ensure that the pH of the composition is within the desired range. Examples of suitable pH-regulating agents include acids , such as inor¬ ganic acids and organic acids. Suitable inoxganic acids in- elude hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid. Suitable organic acids include carboxylic acids, for example, Ci to Ci0 carboxylic acids. Examples in¬ clude formic acid, acetic acid, benozoic acid and citric acid. Alkylsulfonic acids may also be employed. Examples include methylsulfonic and ethylsulfonic acid. Preferred acids are citric acid, hydrochloric acid, phosphoric acid, formic acid, methylsulfonic acid, and benzoic acid. Espe¬ cially preferred is citric acid.
The fabric softening composition may also contain a thicken¬ ing agent. Suitable thickening agents include cellulosic derivatives. Examples include hydroxy methyl cellulose, hy¬ droxy ethyl cellulose, hydroxy ethyl methyl1 cellulose and hydroxy propyl methyl cellulose. When present, the thicken- ing agent is present in an amount of from 0.01 to 1 % by weight, preferably from 0.05 % to 0.5 % b;y weight of the fabric softening composition.
The fabric softening composition may also contain a polyeth- ylene glycol. The polyethylene glycol preferably has a mo¬ lecular weight range of from 500 to 100,000, preferably from 1,000 to 50,000, more preferably from 1,500 to 10,000, and most preferably 4,000. When present, typical levels of polyethylene glycols are from 0.01 to 1 % toy weight, pref- erably from 0.05 % to 0.5 % by weight of the fabric soften¬ ing composition.
Stabilisers may also optionally be added to the fa.bric- softening composition. When used, the stabiliser will help to achieve the desired finished product viscosity and εstabi- lise the finished product to storage. Stabilisers are typi¬ cally selected from single long chain alkyl cationic surfac¬ tants, non-ionic alkoxylated surfactants, amine 02cid.es, fatty acids, and mixtures thereof. Stabilisers are prefera¬ bly used in amounts of from 0 to 15 %, preferably from 0.5 to 5 % by weight of the composition.
The fabric softening composition may optionally include an inorganic viscosity control agent. These agents act like or augment the effect of stabilisers. Examples of such agents include water-soluble, ionisable salts.
A wide variety of ionisable salts can be used. Exampl.es of suitable salts are the halides of the Group IA and HA. met¬ als of the Periodic Table such as calcium chloride, rnagne- sium chloride, sodium chloride, potassium bromide, and lith¬ ium chloride. The amount of ionisable salts used depends on the amount of active ingredients used in the fabric soften¬ ing composition and can be adjusted according to the desires of the formulator. Typical levels of salts used are from 20 to 2000 parts per million (ppm) , preferably from 20 to 1100 ppm, by weight of the composition.
Alkylene polyammonium salts can be incorporated in the fab¬ ric softening composition to give viscosity control in addi- tion to or in place of the water-soluble, ionisable salts
above. In addition, these agents can act as scavengers, forming ion pairs with anionic detergent carried over from the main wash, in the rinse and on the fabrics, and may im¬ prove softness performance. These agents may stabilise the viscosity over a broader range of temperature, especially at low temperatures, compared to the inorganic electrolytes.
Specific examples of alkylene polyammonium salts include 1- lysine monohydrochloride and 1, 5-diammonium 2-methyl pentane dihydrochloride.
An antifoam agent may be included in the fabric softening composition to avoid excess generation of foam during the rinse cycle. Preferably up to 5%wt, ideally less than 3%wt or 2%wt. Typically such agents are silicones.
The term "silicone" has become a generic term which encom¬ passes a variety of relatively high-molecular weight poly¬ mers containing siloxane units and hydrocarbyl groups of various types. Generally, the silicone antifoam agents can be described as siloxanes having the general structure: wherein n is from 20 to 2,000, and where each R independ¬ ently can be an alkyl or an aryl radical . Examples of such substituents are methyl, ethyl, propyl, isobutyl, and phenyl. Preferred polydiorganosiloxanes are polydimethylsi¬ loxanes having trimethylsilyl endblocking units.
The antifoam agent may further comprise, as a water-soluble or water-dispersible carrier, a surfactant-containing solu- tion. The surfactant may be selected from nonionic, ani-
onic, cationic, ampholytic, zwitterionic and semi-polar sur¬ factants.
The fabric softening composition may include a hydrotrope. Examples of suitable hydrotropes are the alkali metal salts of a benzene, cumene, toluene and xylene sulfonate, ideally the sodium salt. Hydrotropes may be added from 0.1 to 10% by weight, ideally no more that 5% by weight, of the fabric softening composition.
The composition may also optionally contain up to 5% by weight of at least one of the following: antioxidants, re¬ ductive agents, surfactants, emulsifiers, bacteriocides, colorants, preservatives, optical brighteners, chelants, natural or synthetic extracts, antifoam agents and mixtures thereof.
The container may be used to dispense the contents of the first compartment separately from the contents of the second compartment. Preferably, however, the container comprises means for dispensing at least part of the contents of the first compartment and at least part of the contents of the second compartment as a mixture. The contents of the first compartment and the contents of the second compartment are preferably mixed prior to use. In one embodiment, a con¬ trolled amount of the contents of the first compartment and a controlled amount of the contents of the second compart¬ ment are mixed prior to use. The controlled amounts may be controlled using a control means, such as a valve.
The container of the present invention may comprise more than two compartments, for example, three, four or five com¬ partments.
The contents of the container may be introduced into the rinse cycle of a washing machine. The contents of the con¬ tainer may be introduced into an aqueous medium and the re¬ sulting aqueous medium may be contacted with a fabric. Preferably, the aqueous medium is at a temperature between 2 to 40 °C, preferably between 5 to 25 0C. Alternatively, the contents of the container may be contacted with a fabric during the course of a hand-wash.
Preferably the ratio of the first composition to the second composition is from 0.8:1 to 1:0.8. Ideally it is 1:1.
The invention is illustrated in the following non limiting examples, in which all percentages are on an active weight % basis unless otherwise stated.
Container
Containers that have at least two compartments are disclosed in the prior art. An example of a two chamber squeezy dis- penser is disclosed in US 5765725. An example of a gravity driven two chamber dispensing system is disclosed in WO 0185595. An example of a spray dispenser having two liquid compartments is disclosed in EP0479451.
We present as a further feature of the invention a container as claimed in any one of the preceding claims comprising means for dispensing at least part of the contents of the first compartment and at least part of the contents of the second compartment either sequentially or at the same time.
EXAMPLE 1
TABLE 1. Compartment 1
TABLE 2. Compartment 2
Esterquat 18 supplied by Undessa SA. Silicone DC 2-8035 supplied by Dow Corning Silicone HV495 supplied by Dow Corning Polycarboxylate Cellosize QP-100 MH supplied by DOW C13-15 8EO Lutensol TO8 supplied by BASF
EXAMPLE 2
TABLE Ia . Compartment 1
Preservative is based on a benzoisothiazolinone, Tergitol is a Cll-15 secondary alcohol. Silicone HV495 supplied by Dow Corning Carbopol is a cross-linked Polycarboxylate. Antifoam is a silicone.
TABLE 2a. Compartment 2
Esterquat 18 supplied by Undessa SA. Silicone DC 2-8035 supplied by Dow Corning Silicone HV495 supplied by Dow Corning