EP1179037A1

EP1179037A1 - Fabric softening compositions

Info

Publication number: EP1179037A1
Application number: EP00929672A
Authority: EP
Inventors: David Stephen Grainger; Frans Jos Unilever Res. Vlaardingen JANSEN
Original assignee: Unilever PLC; Unilever NV
Current assignee: Unilever PLC; Unilever NV
Priority date: 1999-05-17
Filing date: 2000-05-03
Publication date: 2002-02-13
Anticipated expiration: 2020-05-03
Also published as: HU228798B1; AU4767900A; DE60026988T2; ATE321835T1; CA2367033A1; HUP0201469A2; AU768506B2; CZ298908B6; GB9911434D0; MY154358A; CA2367033C; PL351739A1; WO2000070004A1; CZ20014054A3; CN1350572A; JP2002544406A; DE60026988D1; ES2258006T3; BR0010574A; CN1225530C

Abstract

The invention provides a fabric softening composition which has an increased resistance to malodour developement and which comprises: i) a liquid or soft solid derivative of a cyclic polyol (CPE) or of a reduced saccharide (RSE) resulting from 35 to 100 % of the hydroxyl groups in the polyol or saccharide being esterified or etherified, the CPE or RSE having 2 or more ester or ether groups independently attached to a C8-C22 alkyl or alkenyl chain, wherein at least one of the chains attached to the ester or ether groups has at least one unsaturated bond; and ii) a deposition aid; and iii) one or more antioxidant(s), wherein the weight ratio of i) to iii) is 20:1 or greater. The invention also provides a method of reducing malodour in a composition comprising a CPE or RSE as defined above by the addition of at least one antioxidant.

Description

FABRIC SOFTENING COMPOSITIONS

Technical Field

The present invention relates to fabric softening compositions, in particular to those that soften without affecting the absorbency of the fabric and which suffer from a reduced tendency to develop malodour during manufacture, storage or use.

Background and Prior Art

Rinse added fabric softener compositions are well known. However, a disadvantage associated with conventional rinse conditioners is that although they increase the softness of a fabric they often simultaneously decrease its absorbency. This means that its ability to take up water decreases. This is particularly disadvantageous with towels where the consumer requires the towel to be soft, and yet, have a high absorbency.

W098/16538 (Unilever) discloses fabric conditioning compositions comprising liquid or soft solid derivatives of a cyclic polyol or a reduced saccharide which give good softening and retain aβsorbency of the fabric.

EP 0 380 406 (Colgate-Palmolive) discloses detergent compositions comprising a saccharide or reduced saccharide ester containing at least one fatty acid chain. WO 95/00614 (Kao Corporation) discloses softening compositions comprising polyhydπc alcohol esters and catiomsed cellulose.

US 5 447 643 (Huls) discloses aqueous fabric softeners comprising noniomc surfactant and mono, di or tπ fatty acid esters of certain polyols.

WO 96/15213 (Kenkel) discloses textile softening agents containing alkyl , alkenyl and/or acyl group containing sugar derivatives, which are solid after esterification, m combination with noniomc and cationic emulsifiers.

Frequently a liquid or soft solid fabric softening agent, e.g. a CPE or RSE as herein-defined which addresses the above absorbency problem, is obtained by using unsaturated, usually predominantly unsaturated , fatty acid chains on the ester or ether functions. However such compositions may suffer from tne development of product malodour upon manufacture, storage or use. This is obviously highly undesirable .

W0 97/13828 (P&G) discloses fabric conditioning compositions comprising a heavy metal sequestran .

W0 96/21714 and WO 96/21715 (P&G) disclose fabric conditioning compositions comprising chelatmg agents.

W0 96/03481 'P&G) discloses fabric conditioning compositions corrronsinq 1 to 20 wt% antioxidant. The present invention is directed towards alleviating the above-mentioned problems.

The principal advantages of the compositions of the present invention are that they soften fabrics without detriment to the absorbency of the fabric, they are easily manufactured and do not suffer from unacceptable levels of malodour development upon manufacture, storage or use.

Definition of the Invention

Thus according to one aspect of the invention there is provided a fabric softening composition comprising:

I) a liquid or soft solid derivative of a cyclic polyol (CPE) or of a reduced saccharide (RSE) resulting from 35 to 100% of the hydroxyl groups in the polyol or saccharide being esterified or etherified, the CPE or RSE having 2 or more ester or ether groups independently attached to a Cg-C₂₂ alkyl or alkenyl chain , wherein at least one of the chains attached to the ester or ether groups has at least one unsaturated bond, and;

ii) a deposition aid; and

m) one or more antioxidant (s)

wherein the weight ratio of i) to m) is 20:1 or greater. It has been found, surprisingly, thac the above compositions provide an unexpected combination of simultaneous fabric softening and retention of absorbency and exhibit improved malodour resistance, even, at elevated temperatures.

According to a further aspect of the invention, there is provided a method of reducing malodour upon manufacture, storage or use m a composition comprising a CPE or RSE as herein described by the addition of a least one antioxidant.

Detailed Description of the Invention

In the context of the present invention the initials CPE or RSE stand for a derivative of a cyclic polyol or of a reduced saccharide respectively which results from 35 to

100% of the hydroxyl groups of the cyclic polyol or reduced saccharide being esterified or etherified, the CPE or RSE having two or more ester or ether groups independently of one another attached to a Q to C₂₂ alkyl or alkenyl chain, and m which at least one of the chains attached to the ester or ether groups has at least one unsaturated bond.

The CPE or RSE

The CPE or RSE used according to the invention does not have any substantial crystalline character at 20 C. Instead it is preferably m a liquid or soft solid state as herein defined at 20°C. The liquid or soft solid (as neremafter defined) CPEs or RSEs of the present invention result from 35 to 100% of the hydroxyl groups of the starting cyclic polyol or reduced saccharide being esterified or etherified with groups such that the CPEs or RSEs are m the required liquid or soft solid state. These groups typically contain unsaturation, branching or mixed chain lengths.

Typically the CPEs or RSEs have 3 or more ester or ether groups or mixtures thereof, for example 3 to 8 , especially 3 to 5. It is preferred if two or more of the ester or ether groups of the CPE or RSE are independently of one another attached to a C₃ to C₂₂ alkyl or alkenyl chain. The Cg to

C₂₂ alkyl or alkenyl groups may be branched or linear carbon chains.

Preferably 35 to 85% of the hydroxyl groups, most preferably 40-80%, even more preferably 45-75%, such as 45-70% are esterified or etherified.

Preferably the CPE or RSE contains at least 35% tπ or higher esters, eg at least 40%.

The CPE or RSE has at least one of tne chains independently attached to the ester or ether groups having at least one unsaturated bond. This provides a cost effective way of making the CPE or RSE a liquid or a soft solid. It is preferred if predominantly unsaturated fatty chains, derived from, for example, rape oil, cotton seed oil, soybean oil, oleic, tallow, palmitoleic, Imoleic, erucic or other sources of unsaturated vegetable fatty acids, are attached to the ester/ether groups .

These chains are referred to below as the ester or ether chains (of the CPE or RSE) .

The ester or ether chains of the CPE or RSE are preferably predominantly unsaturated. Preferred CPEs or RSEs include sucrose tetratallowate , sucrose tetrarapeate , sucrose tetraoleate, sucrose tetraesters of soybean oil or cotton seed oil, cellobiose tetraoleate, sucrose tπoleate, sucrose tπapeate, sucrose pentaoleate, sucrose pentarapeate , sucrose hexaoleate, sucrose hexarapeate, sucrose tπesters, pentaesters and hexaesters of soybean oil or cotton seed oil, glucose tiroleate, glucose tetraoleate, xylose tπoleate, or sucrose tetra-,trι-, penta- or hexa- esters with any mixture of predominantly unsaturated fatty acid chains . The most preferred CPEs or RSEs are those with monosaturated fatty acid chains, i.e. where any polyunsaturation has been removed by partial hydrogenation. However some CPEs or RSEs based on polyunsaturated fatty acid chains, eg sucrose tetralmoleate, may be used provided most of the polyunsaturation has been removed by partial hydrogenation .

The most highly preferred liquid CPEs or RSEs are any of the above but where the polyunsaturation has been removed through partial hydrogenation. Preferably 40% or more of the fatty acid cnams contain an unsaturated bond, more preferably 50% or more, most preferably 60% or more. In most cases 65% to 100%, e.g. 65% to 95% contain an unsaturated bond.

CPEs are preferred for use with the present invention. Inositol is a preferred example of a cyclic polyol. Inositol derivatives are especially preferred.

In tne context of the present invention, -he term cyclic polyol encompasses all forms of sacchaπoes . Indeed sacchaπdes are especially preferred for use with this invention. Examples of preferred saccharides for the CPEs or RSEs to be derived from are monosaccharides and disaccharides .

Examples of monosaccharides include xylose, arabmose, galactose, fructose, sorbose and glucose. Glucose is especially preferred. Examples of disaccnaπdes include maltose, lactose, cellobiose and sucrose. Sucrose is especially preferred. An example of a reduced saccharide is sorbitan .

The liquid or soft solid CPEs can be prepared by methods well known to those skilled in the art. These include acylation of the cyclic polyol or reduced saccharide with an acid chloride; trans-esteπfication of the cyclic polyol or reduced saccharide fatty acid esters using a variety of catalysts; acylation of the cyclic polyol or reduced saccharide with an acid anhydride and acylation of the cyclic polyol or reduced saccharide with a fatty acid. See for instance US 4 386 213 and AU 14416/88 (both P&G) .

It is preferred if the CPE or RSE has 3 or more, preferably 4 or more ester or ether groups. If the CPE is a disaccharide it is preferred if the disaccharide has 3 or more ester or ether groups. Particularly preferred CPEs are esters with a degree of esteπfication of 3 to 5, for example, sucrose tri, tetra and penta esters.

Where tne cyclic polyol is a reducing sugar it is advantageous if each ring of the CPE has one ether or ester group, preferably at the Ci position. Suitable examples of such compounds include methyl glucose derivatives.

Examples of suitable CPEs include esters of alkyl (poly) glucosides , m particular alkyl glucoside esters having a degree of polymerisation from 1 to 2.

The length of the unsaturated (and saturated if present) chains m the CPE or RSE is C₈-C₂₂, preferably C₁₂-C₂₂. It is possible to include one or more chains of Ci-Cβ, however these are less preferred.

The liquid or soft solid CPEs or RSEs of the present invention are characterised as materials having a solιd:lιquιd ratio of between 50:50 and 0:100 at 20 C as determined by T₂ relaxation time N R, preferably between 43:57 and 0:100, most preferably between 40:60 and 0:100, such as, 20:80 and 0:100. The T₂ N R relaxation time is commonly used for characterising solid: liquid ratios m soft solid products such as fats and margarines. For the purpose of the present invention, any component of the signal with a T₂ of less than 100 μs is considered to be a solid component and any component with T₂ ≥ 100 μs is considered to be a liquid component.

For the CPEs and RSEs, the prefixes (e.g. tetra and penta) only indicate tne average degrees of esterification. The compounds exist as a mixture of materials ranging from the monoester to the fully esterified ester. It is the average degree of esterification which is used herein to define the CPEs and RSEs .

The HLB of the CPE or RSE is typically between 1 and 3.

The CPE or RSE s preferably present in the composition m an amount of 0.5-50% by weight, based upon tne total weight of the composition, more preferably 1-30% by weight, such as 2-25%, eg 2-20%.

The CPEs and RSEs for use m the compositions include those recited m the following examples, including, sucrose tetraoleate, sucrose pentaerucate , sucrose tetraerucate and sucrose pentaoleate.

The Deposition Aid In the context of the present invention a deposition aid is defined as any material that aids deposition of the selected CPE or RSE onto a fabric during the laundering process.

The deposition aid may be selected from cationic compounds, such as cationic surfactants, noniomc surfactants, anionic surfactants, polymeric deposition aids or mixtures thereof. Quaternary ammonium compounds have been found to be particularly advantageous. A class of preferred deposition aids is fabric softening compounds.

It is preferred if the deposition aid is cationic m nature. If a cationic surfactant or cationic softening aid is not present m the formulation it is preferred if a cationic polymeric deposition aid is present. Most preferably the deposition aid is both cationic m nature and is a fabric softening compound.

Mixtures of deposition aids may be used, for example, a mixture of a cationic surfactant and a noniomc surfactant, or a fabric softening compound and a polymeric deposition aid.

Suitable cationic deposition aids include water soluble single chain quaternary ammonium compounds. Examples include cetyl trimethyl ammonium chloride, cetyl trimethyl ammonium bromide, or any of those listed m European Patent No. 258 923 (Akzo Nobel) .

However, it is preferred if the deposition aid is a substantially water insoluble fabric softening compound. In particular substantially water insoluble quaternary ammonium materials comprising a single alkyl or alkenyl chain having an average length equal to or greater than C₂₀ are preferred. Even more preferable are compounds comprising a polar head group and two alkyl or alkenyl chains each having an average chain length equal to or greater than C₁₄.

Preferred fabric softening deposition aids have two long alkyl or alkenyl chains with an average chain length equal to or greater than C₁₄. More preferably each chain has an average chain length greater than Ciβ • Most preferably at least 50% of each long chain alkyl or alkenyl group has a chain length of Cis .

It is preferred if the long chain alkyl or alkenyl groups of the fabric softening deposition aid are predominantly linear .

The fabric softening deposition aids used m the compositions of the invention are molecules which provide excellent softening.

"Substantially water insoluble" fabric compounds m the context of this invention are defined as fabric compounds having a solubility less than 1 x 10 wt% m demmeralised water at 20 C. Preferably the fabric softening deposition

-4 aids have a solubility less than 1 x 10 wt% Most preferably the fabric softening deposition aids have a solubility at 20 C m demmeralised water from 1 x 10 to 1 x 10 ^" wt%.

Preferred fabric softening deposition aids are quaternary ammonium compounds, preferably those with at least one ester link.

It is especially preferred if the fabric softening deposition aid is a water insoluble quaternary ammonium material which comprises a compound having two C₁₂-₁₈ alkyl or alkenyl groups connected to the molecule via at least one ester link. It is more preferred if the quaternary ammonium material has two ester links present. An especially preferred ester-linked quaternary ammonium material for use m the invention can be represented by the formula (I) :

R

R (CH₂) X Formula

wherein each R group is independently selected from C₁-₄

alkyl, hydroxyalkyl or C₂-₄ alkenyl groups; and wherein each R group is independently selected from Cg_28 alkyl or alkenyl groups;

0 0

T is -O-C- or ^•0-

X is any suitable anion and n is 0 or an integer from 1-5.

Preferred materials of this class include

Di (tallowoyloxyethyl ) dimethyl ammonium chloride and Methyl bis- [ethyl ( tallowyl ) ] -2 -hydroxyethyl ammonium methyl sulphate .

A second preferred type of quaternary ammonium material can be represented by the formula (II) :

OOCR

: R^J ₃N⁺— > CH 2Jn" CH X Formula (II)

CH₂OOCR

1 - 2 wherein R , n, X and R are as defined above.

It is advantageous for environmental reasons if the quaternary ammonium material is biologically degradable.

Preferred materials of this class such as 1,2 bis [hardened tallowovloxv] -3 - trimethylammonium DroDane chloride and their method of preparation are, for example, described in

US 4 137 180 (Lever Brothers) . Preferably these materials comprise small amounts of the corresponding monoester as described m US 4 137 180 for example 1-hardened tallowoyloxy -2 -hydroxy 3 - tπmethylammonium propane chloride .

The fabric softening deposition aid of the composition may also be compounds having the formula \III) :

0 0 R^'

(R -C-0-)_mA(-0-C-B-N -R )_n X Formula (III)

R

wherein X is an anion, A is an (m+n) valent radical remaining after the removal of (m+n) hydroxy groups from an aliphatic polyol having p hydroxy groups and an atomic ratio of carbon to oxygen in the range of 1.0 to 3.0 and up to 2 groups per hydroxy group selected from ethylene oxide and propylene oxide, m is 0 or an integer from 1 to p-n, n is an integer from 1 to p-m, and p is an integer of at least 2,

B is an alkylene or alkylidene group containing 1 to 4 carbon atoms,

R , R , R and R are, independently from each other, straight or brancned cr.am C₁-C₄₃ alkyl or alkenyl groups, optionally with substitution by one or more functional groups and/or interruption by at most 10 ethylene oxide and/or propylene oxide groups, or by at most two functional groups selected from

0 0 0 0 0

I! II II i i II II

-C-0-, -0-C-, -C-N-, -N-C-, and -0-C-O-

11 12 or R and R may form a ring system containing 5 or 6 atoms m the ring, with the proviso that the average compound either has at least one R group having 22-48 carbon atoms, or at least two R groups having 16-20 carbon atoms, or at least three R groups having 10-14 carbon atoms. Preferred compounds of this type are described m EP 638 639 (Akzo) .

The deposition aid may also comprise a mixture of different fabric softening compounds, for example a mixture of compounds of Formula (I) and Formula (II) .

The deposition aid may also be a noniomc surfactant, such as a noniomc ethoxylated surfactant having an HLB of from about 10 to about 20. It is advantageous f the surfactant alkyl group contains at least 12 carbon acorns.

Suitable polymeric deposition aids for use with the invention include cationic and noniomc polymeric deposition aids .

Suitable cationic polymeric deposition aids include cationic guar polymers such as; the Jaguar series of polymers (ex Rhodia) , cationic cellulose derivatives such as Celquats, (ex National Starch) , Ucare polymers (ex Amerchol) , cationic starches e.g. potato starch such as SoftGels and Solvitose such as BDA (ex Avebe , C* bond polymers series from Cerestar, cationic pclyacrylamides such as PCG (ex Allied Colloids), Flocaid series of polymers (ex National Starch) and cationic chitosan and derivatives. Cationic polymeric aids are particularly preferred m the absence of any other cationic material m the composition.

Suitable noniomc deposition aids include Pluromcs (ex BASF), dialkyl PEGs , cellulose derivatives as described m GB 213 730 (Unilever; , hydroxy ethyl cellulose, starch, and hydrophobically modified noniomc polyols such as Acusol 880/882 (ex Rohm & Haas) .

Mixtures of any of the aforementioned deposition aids may be used .

In the fabric softening compositions the weight ratio of CPE or RSE to deposition aid is preferably within the range of from 15:1 to 1:10, more preferably within the range from 10:1 to 1:5, most preferably 8:1 to 1:3.

If a composition is required to give particularly high absorbency to fabrics it is advantageous if the weight ratio of CPE or RSE to deposition aid is at least 1:1 (especially if the deposition aid is a fabric softening compound) .

If a highly softening composition is required it is advantageous if the weight ratio of a softening deposition aid to CPE or RSE is at least 2:3, oreferaolv at least 1:1. To give excellent softening and hydrophobicity to fabrics it is preferred if the weight ratio of softening deposition aid to CPE or RSE s from 3:2 to 1:10, more preferably from 2:3 to 1:10.

The fabric softening compositions comprise one or more antioxidants m a weight ratio to the CPE or RSE of 20:1 or more .

The deposition aid is preferably present in the compositions m an amount of 0.05-15% by weight, based upon the total weight of the composition, more preferably 0.1-10%, such as 0.5-7.5%.

Antioxidant

Any suitable antioxidant may be used according to the invention. Preferably the antioxidant comprises at least one initiation inhibitor antioxidant or at least one propagation inhibitor. Mixtures of these two types of antioxidants have been found to be particularly beneficial, especially m reducing medium to long term malodour. Any antioxidant referred to in the following examples may be used.

The compositions preferably comprise 0.0001% to 1% by weight (m total) , based on the total weight of the composition, of antioxidants, more preferably 0.00015% to 0.75%, even more preferably 0.002 to 0.5%, e.g. 0.002 to 0.45%.

It has been found that initiation inhibitors antioxidants can give good short and long term malodour suppression but a mixture of propagation inhibitor and initiation inhibitor antioxidants can give a surprisingly good short and long term malodour suppression.

Suitable initiation inhibitor antioxidants include peroxide decomposers (e.g. sulphides, aryl and alkyl phosphites, metal salts of some thiodipropionates , xanthates and dithiophosphates) .

Suitable peroxide decomposers include (RO₂CCH₂CH₂) ₂ ^s where

R=Ci₂H₂₅, C₁₄H₂₉ o C₁₈H₃₇ i.e. TNPP (tris- nonylphenylphosphite) available as Irgafos 186; Sandostab P- EPQ; and Irgafos P-EPQ respectively. Where used, peroxide decomposers are preferably present at a level of between 0.001% to 0.5% by weight, most preferably 0.005% to 0.1%.

Another type of suitable initiation inhibitor antioxidant are metal ion sequestrants or deactivators . Suitable such types include N, N ' -dιsalιcylιdene-1 , 2 -propanediamme ; oxalyl bis- (benzylidenehydrazide) ; ethylenediammetetraacetic acid (EDTA) ; ethylenediamme- N, N ' -disuccimc acid (EDDS); N-hydroxyethylene-diamme triacetic acid; mtrilotriacetic acid (NTA) ; ethylene diamme tetrapropiomc acid; ethylenediamme-N, N ' -diglutamic acid; 2 -hydorxypropylenediamme-N, N ' -disuccimc acid; triethylenetriamme hexacetic acid; diethylenetπamme pentacetic acid (DETPA) ; trans 1,2-dιammocyclohexane- N, N, N X N ' - tetraacetic acid; ethanol diglyc e; ethylenediamme tetrakis (methylene phosphonic acid) (EDTMP) ; 1-hydroxyethane 1,1 diphosphonic acid (HEDP) ; hydroxyethane dimethylenepnosphomc acid; glucoic acid; citric acid; tartaπc acid; isopropyl citric acid; oxydisuccimc acid; dipicolimc acid; 4,5 dihydroxy-m-benzenesulphomc acid; 8- hydroxyqumolme ; sodium dithiocarbamate ; sodium tetraphenylooron; ammonium mtrosophenyl hydroxylamme; ethylene diamme mono succimc acid (EDMS) ; lmmodisuccimc acid sodium salt (IDS Na salt); Tetrakis [methylene (3 , 5-dι- tert -butyl -4 -hydroxyhydrocinna ate) ] methane (Irganox 1010); Tetrakis [methylene (3 , 5-dι- tert -butyl -4 - hydroxyhydrocmnamate) ] methane ; 1,3, 5- trimethyl -2 , 4 , 6-trιs- (3X5' di-tert-butyl -4 ' -hydroxybenzyl ) benzene (Irganox 1330) and diethylene triammepenta (methylene phosphonate) (Dequest 2066) Metal ion sequestrants are preferably present at a level of between 0.0001% to 0.5% by weight, based on the total weight of the composition, most preferably 0.005% to 0.1%.

Propagation inhibitor antioxidants consist primarily of hindered phenols/polyphenols . These can include those which are commonly used m the foods or plastics industries, such as butylated hydroxyanisole (BHA) ; butylated hydroxytoluene (BHT) ; tert -butyl hydroqu one (TBHQ) ; tocopherols ; tocotπenols ; ascorbic acid; ascobyl palmitate; octyl gallate; propyl gallate; lauryl gallate; N, N-bis (ethyl 3 5' -di -tert -butyl -4 -hydroxybenzoate; 2- (N, N-dimethyl - ammo) ethyl 3 5' -di-tert -butyl -4 ' hydroxybenzoate-N- cocoamme; 2 - (N-methyl -N-cocammo) ethyl 3 ' , 5 ' -di-tert-butyl- 4 ' -hydroxybenzoate ; 2,2' -methylenebis (4 -methyl -6-t- butylphenol) , 4 , 4 ' -butylidenebis (2 -tert-butyl-5- methylphenol) , n-octadecyl 3 , 5-dι-tert-butyl-4 - hydroxyhydrocmnamate , 1,1,3 - tπs (3 - tert-butyl -4 -hydroxy-6- methylphenyl ) butane .

Inhibitor antioxidants are preferably present at a level of 0.0001% to 0.5% by weight, based on the total weight of the composition, more preferably 0.0002% to 0.05%, most preferably 0.0002% to 0.02%.

The weight ratio of the initiation inhibitor X) to the propagation inhibitor (ii) is preferably within the range 10:1 to 1:10, more preferably 10:1 to 1:5, even more preferably 8:1 to 1:1, e.g. 6:1 to 1:1. The weight ratio of CPE or RSE to total antioxidant is 20:1 or greater, preferably 50:1 or greater, more preferably 75:1 or greater. The weight ratio may be as high as 1500:1 or greater. It is preferred that the weight ratio has an upper limit of 3000:1, e.g. 2500:1.

Composition pH

The compositions of the invention preferably nave a pH from 1.5 to 7, more preferably from 1.5 to 5.

Other Ingredients

The compositions can also contain fatty acids, for example Cβ - C₂₄ alkyl or alkenyl monocarboxylic acids, or, polymeric carboxylic acids. Preferably saturated fatty acids are used, particular, hardened tallow Cι₆-C_ι8 fatty acids.

The composition can also contain one or more optional ingredients, selected from electrolytes, non-aqueous solvents, pH buffering agents, perfumes, perfume carriers, fluorescers, colorants, hydrotropes, antifoam g agents, antiredeposition agents, polymeric and other thickeners, enzymes, optical brightening agents, opacifiers, anti- shrinking agents, anti-wrmkle agents, anti-spottmg agents, germicides, fungicides, anti -corrosion agents, drape imparting agents, antistatic agents, sunscreens, colour care agents and ironing aids.

If the product s a liquid it may be advantageous if a viscosity control agent s present. Any viscosity control agent used with rinse conditioners is suitable for use with the present invention, for example biological polymers such as Xanthum gum (Kelco ex Kelsan and Rhodopol ex Rhone- Poulenc) , Guar gum (Jaguar ex Rhone-Poulenc) , starches and cellulose ethers. Synthetic polymers are useful viscosity control agents such as polyacrylic acid, poly vinyl pyrrolidone, polyethylene, carbomers, cross linked polyacrylamides such as Acosol 880/882 polyethylene and polyethylene glycols.

It is preferred that the compositions are substantially free of bleaches. Preferably the compositions are entirely free of bleaches .

Also suitable as viscosity modifiers are decoupling polymers and deflocculatmg polymers.

Product Form

The compositions may be m any form conventionally used for fabric softening compositions e.g., powder, paste, gel or liquid. Liquids, especially emulsions are preferred.

The compositions may be prepared by any suitable method. Where the antioxidant is oil soluble, e.g. the propagation inhibitor, the antioxidant is suitably pre-added with the CPE or RSE. Where the antioxidant is water soluble, e.g. the initiation inhibitor, especially metal sequestrants , the inhibitor is typically post-dosed to a pre-formed emulsion containing the CPE or RSE. Examples

The invention is illustrated by the following non-limiting examples. Further examples within the scope of the present invention will be obvious to the man skilled the art.

Examples 1-13 and 14-24

The effect of the anti-oxidant m reducing malodour development on storage m faoric softening compositions comprising a CPE of the and a deposition aid is demonstrated below.

All %'s are by weight based on the total weight of the composition and represent the amount of active compound. Examples 1 and 14 are controls which do not contain antioxidant. In Ryoto 0-170, 85% or greater of the fatty acid chains contain an unsaturated bond.

Examples 2 to 13 were prepared by dissolving the propagation inhibitor antioxidant (Irganox 1330 or Irganox 1010) m the CPE (Ryoto 0-170) and adding this to a separate mixture of a cationic and water (in an amount to make the composition up to 100 weight %) . The resultant composition was mixed using a low shear Heidolph mixer to produce an emulsion.

In examples 6 to 13 , the initiation inhibitor antioxidant (Dequest 2066) was post-dosed to this emulsion.

Examples 14 to 24 were prepared by mixing the cationic surfactant (CTAC) with water and then addinα to this mixture the CPE (Ryoto O-170) at room temperature under conditions of high shear to produce an emulsion.

In examples 15 and 22 to 24, the propagation inhibitor antioxidant (Irganox 1010) was dissolved m the CPE prior to emulsification.

In example 16 to 24, the initiation inhibitor antioxidant (Dequest 2066, DTPA or Na IDS) was post-dosed into the final emulsion.

The formulat ions of Examples 1 - 13 and 14 - 24 are shown m Tables 1 and 2 respect ively .

Table 1

sucrose pentaoleate (from Mitsubishi-Kagaku Food Corporation) cetyl trimethyl ammonium chloride; from Aldrich (as a 25% solution) . diethylene triammepenta (methylene phosphonate); available from solutia. "A" is Irganox 1330; 1 , 3 , 5-tπmethyl-2 , 4 , 6- tπs- (3 ' , 5 ' di- tert -butyl -4 ' -hydroxybenzyl ) benzene .

"B" is Irganox 1010; Tetrakis [methylene (3 , 5-dι-tert-butyl • 4 -hydroxyhydrocmnamate )] methane (Both from Ciba Geigy) .

Table 2

diethylene triamme-N, N, N ' , N ' ' , N ' ' -pentakis methylene phosphoric acid (from Solutia) diethylene tπamme pentaacetate (from Akzo Nobel) lmmodisuccimc acid sodium salt (from Bayer)

The samples were stored m screw-top glass bottles at 37°C to 45 °C. At the intervals given m Tables 3 and 4 the bottles were removed from storage and the samples assessed for the development of malodour (which was determined by assessing the level of a rancid 'fatty' smell present) . Before each assessment the samples allowed to equilibrate at room temperature. The malodour was assessed at room temperature by sniffing the odours from the equilibrated sample and assigning a value between 0 and 5 to indicated the level of malodour. Zero was given if the sample had no perceivable rancid smell and five was given for a very strong rancid smell . At least ten people assessed each sample and the average value was calculated from their response.

As a marker of a value of 5 for a rancid fat an emulsion containing 1% CTAC and 4.5% by weight Pπolube 1446

(neopentyl glycol dioleate ex Unichema) was stored at 45 °C for 4 weeks.

The malodour values of Examples 1 - 13 and 14 - 24 are shown m Tables 3 and 4 respect ively . Table 3 below shows the malodour values determined for examples 1-13 over a 27 week testing period with storage between 37 C-45°C.

ro cV Λ

EH The above results demonstrate the suppression of malodour m a sample containing a predominantly unsaturated CPE and a deposition aid by the addition of an antioxidant. Where the antioxidant is a mixture of a propagating inhibitor and an initiation inhibitor then longer term malodour suppression was achieved.

Furthermore advantageous synergistic results were obtained by using 0.01% by weight initiation inhibitor with 0.00225- 0.0045% by weight propagation inhibitor (see examples 6-9) .

Table 4 below shows the malodour values determined for examples 14-24 over a 4 week testing period with storage at

45°C.

Table 4

The results m table 4 demonstrate that wnen the only antioxidant present is an initiation inhibitor, odour suppression was achieved. Where the antioxidant comprised both a propagation and an initiation inhibitor, significantly improved odour suppression was obtained. This is surprising given that little or no odour suppression was observed when the only antioxidant present was the propagation inhibitor.

Therefore, there is a clear synergistic effect between the propagation and the initiation inhibitor.

Further compositions which have improved malodour suppression m the presence of propagation and the initiation inhibitor are given m the following examples.

Examples 25 to 34

Examples 25 to 28 in Table 5 below were prepared by mixing the listed components together m water.

Table 5 (Mixtures with CTAC)

Irganox 1010, Dequest 2066 and CTAC are described above.

The Ryoto products are available from Mitsubishi -Kagaku Food

Corporation .

The Examples m Tables 6 to 9 below were prepared by heating the ingredients together at 80°C, and mixing at high shear.

Table 6: Mixtures with HEQ (fabric softening compound)

HEQ is 1,2 bis [hardened tallowoyloxy] -3 - trimethylammonium propane chloride available from Hoechst .

Table 7; mixtures with Arquad 2-HT

Arquad 2-HT is ditallow dimethyl ammonium chloride Example 35

Example 35 was prepared as a 5% total active emulsion/dispersion m water comprising 4.5% sucrose tetraerucate (oily liquid, Ryoto ER 290), 0.5% CTAC, 0.01% Dequest 2066, 0.0045% Irganox 1010 and 0.2% of a polymer deposition aid as given below: -

Example 35a FlocAid 34 (ex National Starch) Example 35b Softgel BDA (ex Avebe)

Example 36

Example 36 was prepared as a 1:4 emulsion/dispersion (5% total active) of DEEDMAC : sucrose pentaoleate (Ryoto 0-170) by mixing at high temperatures. To this is added , 0.01% Dequest 2066 and 0.004% Irganox 1010.

Example 37

A fully formulated fabric softening composition as according to the present invention was prepared as below:

% by weight

Genapol C150^a 1.6 b ABS 0.4

Ryoto O-170 15.4 c Cationic potato starch 2 Perfume 0.96 Preservative Minor Dye Minor

Na IDS 0.01 Irganox 1330 0.015 Water Balance

Coco alcohol 15EO (ex Claπant) dodec l benzene sulphomc acid sodium salt (ex Aldrich Chemical Company) ^CSoftqel BDA (ex Aveoe)

Example 38

Table 8 shows the T₂ NMR solid: liquid ratio of CPEs and RSEs used according to the present invention. The ratios were measured at 20 C. The degree of esterification /etheπfication is stated.

Table 8

The Ryoto materials are described above . Examples 39 to 52

All the compositions m table 9 were prepared as follows: The propagation inhibitor was dissolved in the sucrose tetraoleate a weight ratio of 99.9:0.1. This mixture was then comelted with the TEA and Coco-15EO and then added to water at 60 C with stirring using a low shear Heidolph mixer. The resulting mixture was stirred for 10 minutes before being cooled to room temperature. Where an initiation inhibitor was used, it was post-dosed to the final mixture as a 5% solution m water with mixing.

Table 9

methyl bis- [ethyl (tallowyl) ] -2 -hydroxyethyl ammonium methyl sulphate (available as a 90% paste under the trade name Rewoquat WE18 from Goldschmidt (ex Witco) ) . a sucrose polyoleate with an approximate degree of esterification of 4. ethylene diamme-N, N' disuccimc acid (from Associated

Octel) . ethylene diamme tetra acetic acid (from Contract

Chemicals) . ethylene diamme tetra (methylene phosphonate) from Solutia.

Table 10 below shows the malodour values determined for examples 39-52 over a 9 week testing period with storage at

45°C.

All samples were stored m loosely closed glass bottles at

45 C. At weekly intervals, the samples were removed form the oven and allowed to cool to room temperature prior to panelling. Malodour scores were ranked on a 0 to 5 basis, whereby 0 = no malodour smell and 5 = extremely strong malodour. The results are given in table 10

Table 10

The results demonstrate that when only the propagation inhibitor was used in the softening compositions, good odour suppression was observed over the 9 week period. When a mixture of the propagation and initiation inhibitors was used m the softening compositions, significantly better odour suppression was observed over the 9 week period.

Claims

1) A fabric softening composition comprising: I) a liquid or soft solid derivative of a cyclic polyol (CPE) or of a reduced saccharide (RSE) resulting from 35 to 100% of the hydroxyl groups m the polyol or saccharide being esterified or etherified, the CPE or RSE having 2 or more ester or ether groups independently attached to a C₈-C22 alkyl or alkenyl chain, wherein at least one of the chains attached to the ester or ether groups has at least one unsaturated bond, and

II) a deposition aid, and

III) one or more antioxidant (s) , wherein the weight ratio of 1) to 111) is 20:1 or greater.

2) A composition according to claim 1 wherein the CPE or RSE contains at least 35% tri or higher esters.

3) A composition according either claim 1 or claim 2 wherein the CPE or RSE has 40-80%, preferably 45-75%, of the hydroxyl groups esterified and/or etherified.

4) A composition according to any one of the preceding claims wherein the CPE OR RSE has 4 or more hydroxy groups esterified or etherified. 5) A composition according to any one of the preceding claims wherein the CPE or RSE is derived from a monosaccharide or disaccharide.

6) A composition according to any one of the preceding claims wherein the deposition aid is selected from cationic surfactants, noniomc surfactants, amonic surfactants, polymeric deposition aids, fabric softening compounds or mixtures thereof .

7) A composition according to claim 6 wherein the fabric softening compounds are quaternary ammonium compounds.

8) A composition according to any one of the preceding comprising 0.5%-50% by weight of the CPE or RSE, preferably l%-30%.

9) A composition according to any one of the preceding claims wherein the one or more antioxidant (s) comprises at least one initiation inhibitor, or at least one propagation inhibitor, or mixtures thereof.

10) A composition according to any one of the preceding claims wherein the composition comprises 0.0001% to 1% by weight of the one or more antioxidant (s) .

11) A composition according to any one of the preceding claims wherein the weight ratio of the CPE or RSE to antioxidant (s) is 50:1 or greater , preferably 75 ;1 or greater. 12) A composition according to any preceding claim which is a liquid, preferably an emulsion.

13) A method of reducing malodour in a composition comprising a CPE or RSE as defined in claim 1 by the addition of at least one antioxidant.

14) A method according to claim 13 wherein the antioxidant is as defined in any one of claims 9 to 11.