LAUNDRY COMPOSITIONS
FIELD OF THE INVENTION This invention relates to a laundry composition. More particularly, the invention is directed to a softening in the wash laundry composition.
BACKGROUND OF THE INVENTION Textile fabrics, including clothes, have traditionally been cleaned with laundry detergents. After cleaning, fabrics can often feel harsh. To prevent the
drawbacks of fabrics feeling harsh after cleaning and especially experienced after multiple wash and wear cycles, technologies have been developed to increase the softness of fabrics, including rinse-added conditioner compositions and softening systems added to the detergent composition. These formulations are sometimes classed as softening in the wash laundry detergents.
Silicone materials such as polydimethylsiloxanes (PDMS) are known as softening materials in laundry.
There is a need to improve product stability of softening in the wash laundry detergents based on silicone softening materials.
We have found that the aforementioned problem can be overcome by virtue of a formulation comprising a betaine functionalised silicone. These formulations provide a product that displays improved stability over the aforementioned prior art.
SUMMARY OF THE INVENTION
In a first aspect, the invention is directed to a laundry detergent composition comprising:- (a) from 1 to 40 wt.% of nonionic surfactant;
(b) from 1 to 40 wt.% of anionic surfactant; and,
(c) from 0.1 to 10 wt.% of a betaine functionalised silicone
Preferably the betaine functionalised silicone is present at a level of from 0.25 to 10 wt.%, more preferably at a level of from 0.25 to 7.5 wt.%, more preferably at a level of from 0.5 to 5 wt.%.
Preferably the nonionic surfactant and the anionic surfactant are each present at a level of from 4 to 40 wt.%, more preferably from 4 to 20 wt.%.
Preferably the nonionic surfactant comprises an alcohol ethoxylate.
Preferably a cationic polymer is present at a level of from 0.1 to 2.5 wt.%. Preferably the detergent composition is a liquid laundry detergent composition.
If the composition is a liquid, then preferably it has a pH of from 6.2 to 9, more preferably from pH 6.5 to 8.5. DETAILED DESCRIPTION OF THE INVENTION
As used herein, the term "comprising" means including, made up of, composed of, consisting and/or consisting essentially of.
All percentages quoted are wt.% based on total amount in the laundry composition unless otherwise stated.
The invention is directed to laundry compositions containing a nonionic surfactant, an anionic surfactant and a betaine functionalized silicone. The composition displays improved stability for the silicone material in comparison to other silicones.
Form of the Invention
The invention can take any of a number of forms that are laundry compositions. Examples include powders, granules, bars, gels and liquids. Preferably the composition is in the form of a liquid laundry product. Preferably they are main wash products. It can take the form of a laundry composition for the main wash, which may be dilutable or non-dilutable. The laundry composition may for example be an isotropic liquid, or a surfactant-structured liquid. Particularly preferred forms of this invention include combination detergent/softener products to provide "softening in the wash".
Preferably the detergent composition is a liquid laundry detergent composition. Preferably the liquid composition has a pH of from 6.2 to 9, more preferably from pH 6.5 to 8.5.
Betaine Functionalised Silicone
The betaine functionalised silicone is present at a level of from 0.1 to 10 wt.%. Preferably the betaine functionalised silicone is present at a level of from 0.25 to 10 wt.%, more preferably at a level of from 0.25 to 7.5 wt.%, even more preferably at a level of from 0.5 to 5 wt.%, most preferably at a level of from 0.5 to 2.5 wt.%.
The silicone has a betaine functionality. The silicone may be any silicone, but preferred silicone backbones are based on polydimethylsiloxane (PDMS), also known as dimethicone. Preferred betaine functionalities have a silicone backbone that is attached to the following preferred betaine structure:
Preferred silicones are Dimethicone Propyl PG-Betaine, available from Evonik under the tradenames TEGOPREN 6950 and REWOCARE 6950.
Surfactants
The detergent composition comprises nonionic surfactant, and anionic surfactant. The nonionic surfactant component preferably comprises alcohol ethoxylate.
The alcohol ethoxylates are formed from the reaction of primary or secondary alcohols with ethylene oxide. Typicially an aliphatic C8 to Ci8 primary or secondary linear or branched alcohol is reacted with ethylene oxide in the required molar amount to produce the alcohol ethoxylate. Preferred alcohol ethoxylates have from 2 to 40, preferably from 3 to 30, more preferably from 5 to 20 ethylene oxide units attached to the aliphatic chain.
The surfactants may be chosen from the surfactants described in "Surface Active Agents" Vol. 1 , by Schwartz & Perry, Interscience 1949, Vol. 2 by Schwartz, Perry & Berch, Interscience 1958, in the current edition of "McCutcheon's Emulsifiers and Detergents" published by Manufacturing Confectioners Company or in
"Tenside-Taschenbuch", H. Stache, 2nd Edn., Carl Hauser Verlag, 1981 .
Preferably the surfactants used are saturated.
Suitable nonionic detergent compounds which may be used include, in particular, the reaction products of compounds having a hydrophobic group and a reactive hydrogen atom, for example, aliphatic alcohols, acids, amides or alkyl phenols with alkylene oxides, especially ethylene oxide either alone or with propylene oxide. Specific nonionic detergent compounds are C6 to C22 alkyl phenol- ethylene oxide condensates, generally 5 to 25 EO, i.e. 5 to 25 units of ethylene oxide per molecule, and the condensation products of aliphatic C8 to C-|8 primary or secondary linear or branched alcohols with ethylene oxide, generally 5 to 40 EO.
Suitable anionic detergent compounds which may be used can be water-soluble alkali metal salts of organic sulphates and sulphonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl portion of higher acyl radicals. Examples of suitable synthetic anionic detergent compounds are sodium and potassium alkyl sulphates, especially those obtained by sulphating higher Cs to C-is alcohols, produced for example from tallow or coconut oil, sodium and potassium alkyl Cg to C20 benzene sulphonates, particularly sodium linear secondary alkyl C-m to C15 benzene sulphonates; and sodium alkyl glyceryl ether sulphates, especially those ethers of the higher alcohols derived from tallow or coconut oil and synthetic alcohols derived from petroleum. The anionic surfactant may also include soaps of C6-C22 fatty acids. The preferred anionic detergent compounds are sodium Cn to C-is alkyl benzene sulphonates and sodium C12 to Ci8 alkyl sulphates. Salts of sulphonates included as hydrotrobes can additionally be considered as anionic surfactants as defined herein. Also applicable are surfactants such as those described in EP-A-328 177 (Unilever), which show resistance to salting-out, the
alkyl polyglycoside surfactants described in EP-A-070 074, and alkyl
monoglycosides.
The nonionic detergent is present in amounts of from 1 to 40 wt.%, preferably from 2 to 35 wt.%, more preferably from 4 to 20 wt.%, or even from 6 to 20 wt.%.
The anionic surfactant is present in amounts of from 1 to 40 wt.%, preferably from 2 to 35 wt.%, more preferably from 4 to 20 wt.%, or even from 6 to 20 wt.%. The total amount of surfactant present in the composition is preferably at least 5 wt.%, more preferably at least 10 wt.%, More preferably the total amount of surfactant is from 15 to 65 wt.%, preferably from 10 to 50 wt.%.
Other surfactants such as cationic surfactants and amphoteric/zwitterionic surfactants such as betaines may also be present in addition to the
aforementioned nonionic and anionic surfactants.
Optional Ingredients
Cationic Polymer
The composition may additionally comprise a cationic polymer.
This term refers to polymers having an overall positive charge.
Preferably the cationic polymer is selected from the group consisting of: cationic polysaccharide polymers, and cationic non-saccharide polymers having cationic protonated amine or quaternary ammonium functionalities that are homo or copolymers derived from monomers containing an amino or quaternary nitrogen functional group polymerised from at least one of the following monomer classes: acrylate, methacrylate, acrylamide, methacrylamide; allyls (including diallyl and methallyl); ethylene imine; and/or vinyl monomer classes, and mixtures thereof.
More preferably the cationic polymer is selected from the group consisting of cationic cellulose polymers, cationic guar polymers, cationic diallyl quaternary ammonium-containing polymers and homo or copolymers of dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate or tert-butylaminoethyl
(meth)acrylate in their quaternary or protonated amine form, and mixtures thereof.
Most preferably the cationic polymer is a cationic polysaccharide polymer. More preferably the cationic polysaccharide polymer is a cationic guar or cationic cellulose polymer. Most preferably the cationic polymer is a cationic cellulose polymer, for example, quaternised hydroxy ethyl cellulose.
The composition may include a single cationic polymer or a mixture of cationic polymers from the same or different classes, i.e. the composition may contain a cationic polysaccharide polymer and a cationic non-polysaccharide polymer.
Cationic Polysaccharide Polymer
The term "cationic polysaccharide polymer" refers to polymers having a
polysaccharide backbone and an overall positive charge. Polysaccharides are polymers made up from monosaccharide monomers joined together by glycosidic bonds.
The cationic polysaccharide-based polymers present in the compositions of the invention have a modified polysaccharide backbone, modified in that additional chemical groups have been reacted with some of the free hydroxyl groups of the polysaccharide backbone to give an overall positive charge to the modified cellulosic monomer unit.
A preferred class of cationic polysaccharide polymers suitable for this invention are those that have a polysaccharide backbone modified to incorporate a quaternary ammonium salt. Preferably the quaternary ammonium salt is linked to the polysaccharide backbone by a hydroxyethyl or hydroxypropyl group.
Preferably the charged nitrogen of the quaternary ammonium salt has one or more alkyl group substituents.
Preferred cationic polysaccharide-based polymers have a guar based, or cellulosic based backbone. Cellulose based cationic polymers are most preferred. Guar is a galactomannan having a β-1 ,4 linked mannose backbone with
branchpoints to a-1 ,6 linked galactose units.
Suitable cationic guar gum derivatives, such as guar hydroxypropyltrimonium chloride, specific examples of which include the Jaguar series commercially available from Rhone-Poulenc Incorporated and the N-Hance series commercially available from Aqualon Division of Hercules, Inc.
An example of a preferred guar based cationic polymer is guar 2-hydroxy-3- (trimethylammonium) propyl ether salt.
Cellulose is a polysaccharide with glucose as its monomer, specifically it is a straight chain polymer of D-glucopyranose units linked via β-1 ,4 glycosidic bonds and is a linear, non-branched polymer. Example cationic cellulose polymers are salts of hydroxyethyl cellulose reacted with trimethyl ammonium substituted epoxide, referred to in the field under the International Nomenclature for Cosmetic Ingredients as Polyquatemium 10 and is commercially available from the Amerchol Corporation, a subsidiary of The Dow Chemical Company, marketed as the Polymer LR, JR, and KG series of polymers. Other suitable types of cationic celluloses include the polymeric quaternary
ammonium salts of hydroxyethyl cellulose reacted with lauryl dimethyl ammonium- substituted epoxide referred to in the field under the International Nomenclature for Cosmetic Ingredients as Polyquatemium 24. These materials are available from Amerchol Corporation marketed as Polymer LM-200.
Typical examples of preferred cationic cellulosic polymers include
cocodimethylammonium hydroxypropyl oxyethyl cellulose,
lauryldimethylammonium hydroxypropyl oxyethyl cellulose,
stearyldimethylammonium hydroxypropyl oxyethyl cellulose, and
stearyldimethylammonium hydroxyethyl cellulose; cellulose 2-hydroxyethyl 2- hydroxy 3-(trimethyl ammonio) propyl ether salt, polyquaternium-4,
polyquaternium-10, polyquaternium-24 and polyquaternium-67 or mixtures thereof. More preferably the cationic cellulosic polymer is a quaternised hydroxy ether cellulose cationic polymer. These are commonly known as polyquaternium-10. Suitable commercial cationic cellulosic polymer products for use according to the present invention are marketed by the Amerchol Corporation under the trade name UCARE.
Other Cationic Polymer Classes
Non-polysaccharide based cationic polymers may also be used. Suitable cationic non-saccharide polymers include those having cationic protonated amine or quaternary ammonium functionalities that are homo or copolymers derived from monomers containing an amino or quaternary nitrogen functional group
polymerised from at least one of the following monomer classes: acrylate, methacrylate, acrylamide, methacrylamide; allyls (including diallyl and methallyl); ethylene imine; and/or vinyl monomer classes, and mixtures thereof.
Preferred cationic non-saccharide polymers include cationic diallyl quaternary ammonium-containing polymers and homo or copolymers of dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate or tert-butylaminoethyl
(meth)acrylate in their quaternary or protonated amine form, and mixtures thereof.
Other suitable cationic polymers for use in the compositions include copolymers of 1 -vinyl-2-pyrrolidone and 1 -vinyl-3-methylimidazolium salt (known as
Polyquatemium-16); copolymers of 1 -vinyl-2-pyrrolidone and dimethylaminoethyl methacrylate (known as Polyquaternium-1 1 ); cationic diallyl quaternary
ammonium-containing polymers, including, for example, dimethyldiallylammonium chloride homopolymer, copolymers of acrylamide and dimethyldiallylammonium chloride (known as Polyquatemium 6 and Polyquatemium 7 respectively);
amphoteric copolymers of acrylic acid including copolymers of acrylic acid and dimethyldiallylammonium chloride (known as Polyquatemium 22), terpolymers of acrylic acid with dimethyldiallylammonium chloride and acrylamide (known as Polyquatemium 39), and terpolymers of acrylic acid with methacrylamidopropyl trimethylammonium chloride and methylacrylate (known as Polyquatemium 47). Preferred cationic substituted monomers are the cationic substituted
dialkylaminoallcyl acrylamides, dialkylaminoallcyl methacrylamides, and
combinations thereof.
The counterion of the cationic polymer is freely chosen from the halides: chloride, bromide, and iodide; or from hydroxide, phosphate, sulphate, hydrosulphate, ethyl sulphate, methyl sulphate, formate, and acetate.
The cationic polymer is present at a level of from 0.1 to 2.5 wt.%, preferably from 0.1 to 2 wt.%, more preferably from 0.2 to 1 wt.%.
Many of the aforementioned cationic polymers can be synthesised in, and are commercially available in, a number of different molecular weights. Preferably the
molecular weight of the cationic polymer is from 10,000 to 2,000,000 Daltons, more preferably from 100,000 to 1 ,000,000 Daltons.
The detergent composition may optionally comprise one or more of the following optional ingredients, shading dye, enzyme, antiredeposition polymer, dye transfer inhibiting polymer, builder, sequestrant, sunscreen and/or soil release polymer.
Builders and sequestrants
The detergent compositions may also optionally contain relatively low levels of organic detergent builder or sequestrant material. Examples include the alkali metal, citrates, succinates, malonates, carboxymethyl succinates, carboxylates, polycarboxylates and polyacetyl carboxylates. Specific examples include sodium, potassium and lithium salts of oxydisuccinic acid, mellitic acid, benzene
polycarboxylic acids, ethylene diamine tetra-acetic acid, diethylenetriamine- pentaacetic acid, alkyl- or alkenylsuccinic acid, nitrilotriacetic acid, and citric acid. Other examples are DEQUEST™, organic phosphonate type sequestering agents sold by Monsanto and alkanehydroxy phosphonates.
Other suitable organic builders include the higher molecular weight polymers and copolymers known to have builder properties. For example, such materials include appropriate polyacrylic acid, polymaleic acid, and polyacrylic/polymaleic acid copolymers and their salts, such as those sold by BASF under the name SOKALAN™. Another suitable builder is sodium carbonate. If utilized, the builder materials may comprise from about 0.5% to 20 wt%, preferably from 1 wt% to 10 wt%, of the composition. The preferred builder level is less than 10 wt% and preferably less than 5 wt% of the composition.
Preferably the laundry detergent formulation is a non-phosphate built laundry detergent formulation, i.e., contains less than 1 wt.% of phosphate.
Shading Dye
Shading dyes deposit to fabric during the wash or rinse step of the washing process providing a visible hue to the fabric. Shading of white garments may be done with any colour depending on consumer preference. Blue and Violet are particularly preferred shades and consequently preferred dyes or mixtures of dyes are ones that give a blue or violet shade on white fabrics. The shading dyes used are preferably blue or violet. The shading dye chromophore is preferably selected from the group comprising: mono-azo, bis-azo, triphenylmethane, triphenodioxazine, phthalocyanin, naptholactam, azine and anthraquinone. Most preferably mono-azo, bis-azo, azine and anthraquinone. Most preferably the dye bears at least one sulfonate group.
Preferred shading dyes are selected from direct dyes, acid dyes, hydrophobic dyes, cationic dyes and reactive dyes. If included, the shading dye is present in the composition in a range from 0.0001 to 0.01 wt %.
Fluorescent Agent
The composition preferably comprises a fluorescent agent (optical brightener). Fluorescent agents are well known and many such fluorescent agents are available commercially. Usually, these fluorescent agents are supplied and used in the form of their alkali metal salts, for example, the sodium salts. The total amount of the fluorescent agent or agents used in the composition is generally from 0.005 to 2 wt.%, more preferably 0.01 to 0.1 wt.%. Preferred classes of fluorescer are: Di-styryl biphenyl compounds, e.g. Tinopal (Trade Mark) CBS-X,
Di-amine stilbene di-sulphonic acid compounds, e.g. Tinopal DMS pure Xtra and Blankophor (Trade Mark) HRH, and Pyrazoline compounds, e.g. Blankophor SN. Preferred fluorescers are: sodium 2-(4-styryl-3-sulfophenyl)-2H-napthol[1 ,2- d]trazole, disodium 4,4'-bis{[(4-anilino-6-(N methyl-N-2 hydroxyethyl) amino 1 ,3,5- triazin-2-yl)]amino}stilbene-2-2' disulfonate, disodium 4,4'-bis{[(4-anilino-6- morpholino-1 ,3,5-triazin-2-yl)]amino} stilbene-2-2' disulfonate, and disodium 4,4'- bis(2-sulfoslyryl)biphenyl.
Perfume
Preferably the composition comprises a perfume. The perfume is preferably in the range from 0.001 to 3 wt.%, most preferably 0.1 to 1 wt.%. Many suitable examples of perfumes are provided in the CTFA (Cosmetic, Toiletry and
Fragrance Association) 1992 International Buyers Guide, published by CFTA Publications and OPD 1993 Chemicals Buyers Directory 80th Annual Edition, published by Schnell Publishing Co.
It is commonplace for a plurality of perfume components to be present in a formulation. In the compositions of the present invention it is envisaged that there will be four or more, preferably five or more, more preferably six or more or even seven or more different perfume components.
In perfume mixtures preferably 15 to 25 wt.% are top notes. Top notes are defined by Poucher (Journal of the Society of Cosmetic Chemists 6(2):80 [1955]). Preferred top-notes are selected from citrus oils, linalool, linalyl acetate, lavender, dihydromyrcenol, rose oxide and cis-3-hexanol.
It is preferred that the laundry treatment composition does not contain a peroxygen bleach, e.g., sodium percarbonate, sodium perborate, and peracid.
Polymers
The composition may comprise one or more polymers. Polymers can assist in the cleaning process by helping to retail soil in solution or suspension and/or preventing the transfer of dyes. Polymers can also assist in the soil removal process. Dye transfer, anti-redeposition and soil-release polymers are described in further detail below.
The composition may comprise one or more polymers. Examples are
carboxymethylcellulose, hydroxyethyl cellulose, hydroxpropyl cellulose, poly(ethylene glycol), polyvinyl alcohol), ethoxylated polyamines,
polycarboxylates such as polyacrylates, maleic/acrylic acid copolymers and lauryl methacrylate/acrylic acid copolymers.
Dye transfer inhibitors
Modern detergent compositions typically employ polymers as so-called 'dye- transfer inhibitors'. These prevent migration of dyes, especially during long soak times. Generally, such dye-transfer inhibiting agents include polyvinyl pyrrolidone polymers, polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N- vinylimidazole, manganese pthalocyanine, peroxidases, and mixtures thereof, and are usually present at a level of from 0.01 to 10 wt.% based on total amount in the laundry composition.
Anti-redeposition polymers
Anti-redeposition polymers are designed to suspend or disperse soil. Typically antiredeposition polymers are ethoxylated and or propoxylated polyethylene imine or polycarboxylate materials, for example, Acrylic acid based homo or copolymers available under the trade mark ACUSOL from Dow Chemical, Alcosperse from Akzonobel or Sokolan from BASF.
Soil Release Polymers
Examples of suitable soil release polymers include graft copolymers of polyvinyl ester), e.g., Ci -C6 vinyl esters, preferably polyvinyl acetate) grafted onto polyalkylene oxide backbones. Commercially available soil release agents of this kind include the SOKALAN type of material, e.g., SOKALAN HP-22, available from BASF (West Germany). Further suitable soil release polymers of a different type include the commercially available material ZELCON 5126 (from DuPont) and MILEASE T (from ICI). If present, the soil release polymer may be included at a level of from from 0.01 to 10 wt.% based on total amount in the laundry composition. Further examples of soil release polymers are terephthalic acid / glycol copolymers sold under the tradenames Texcare, Repel-o-tex, Gerol, Marloquest, Cirrasol.
Hydrotrope
The detergent composition, especially when a liquid composition may optionally include a hydrotrope, which can prevent liquid crystal formation. The addition of the hydrotrope thus aids the clarity/transparency of the composition. Suitable hydrotropes include but are not limited to propylene glycol, ethanol, glycerol, urea, salts of benzene sulphonate, toluene sulphonate, xylene sulphonate or cumene sulphonate. Suitable salts include but are not limited to sodium, potassium, ammonium, monoethanolamine, triethanolamine. Salts of sulphonates can also be considered as anionic surfactants as defined herein. Preferably, the
hydrotrope is selected from the group consisting of propylene glycol, xylene sulfonate, ethanol, and urea to provide optimum performance. The amount of the hydrotrope is generally in the range of from 0 to 30%, preferably from 0.5 to 30%, more preferably from 0.5 to 30%, most preferably from 1 to 15%.
Enzymes
Enzymes can also be present in the formulation. Preferred enzymes include protease, lipase, pectate lyase, amylase, cutinase, cellulase, mannanase. If
present the enzymes may be stabilized with a known enzyme stabilizer for example boric acid. The choice of enzymes may be influenced by the cationic polymer which is present. Examples
Various silicones were tested for compatibility with two anionic/nonionic surfactant laundry formulation bases, Ύ' and 'Z', corresponding to high and low surfactant concentrations respectively.
20g of the base formulation was weighted into a vial, to which an emulsified silicone was added. The formulation is stirred then allowed to stand at room temperature. The formulation was visually observed to examine stability. The formulation was either deemed clear, hazy, or phase separated. The observation was repeated after 2 days (for base formulation Ύ'), or 1 week (for base formulation 'Z'). The product was deemed stable if on both observations the formulation was clear.
The silicones used in examples A-G were softening silicones known in the prior art. Example 1 uses the betaine functionalised silicone. The experiment used emulsified silicones. The silicones that came emulsified were used 'as is'. The silicones that were not emulsified were emulsified using Tergitol TMN-6.
The following test silicones were used:-
1 PDMS refers to Polydimethylsiloxane;
* 1 kcSt refers to the viscosity of the mateiral (1 k cSt = 1 ,000 centi Stokes etc .);
2 PDMS, Arristan and Finish are examples of softening silicones, and were sourced from Dow Chemical, CHT-Beitlich and Wacker respectively;
3 Rewocare 6950 was sourced from Evonik Silicones C, D, G and 1 were supplied as emulsions, silicones A, and E were emulsified using Tergitol TMN-6, and silicones B and F were alternatively emulsified using a combination of dipropylene glycol and Tergitol TMN-6 to reflect the product characteristics of the supplied Rewocare 6950 (which is supplied as a emulsion including dipropylene glycol).
The results for silicone incorporation in base formulation Ύ' were:-
Example Initial Observation 2 Day Observation
A Haze Separation
B Haze Separation
C Haze Separation
D Haze Separation
E Haze Separation
F Haze Separation
G Haze Separation
1 Clear Clear
Only the betaine functional ised silicone gave an acceptable clear product. The rest were unstable due to haze and ultimately phase separation.
The results for silicone incorporation in base formulation 'Z' were:-
Again, only the betaine functional ised silicone gave an acceptable clear product. The rest were unstable due to haze and ultimately phase separation.