The present invention relates to fabric washing detergent compositions. In particular, the invention relates to fabric washing detergent compositions containing photofading inhibitors.
The fading of coloured articles by sunlight is a major consumer problem in many parts of the world. Thus susceptible articles from temperate and low latitude regions in addition to those from the tropics can be severely faded during wear or whilst drying. Sun fading of fabrics is of specific concern to consumers because the contrast between exposed and unexposed areas makes it particularly noticeable. e.g on collars, inside versus outside of garments, and on wrap around garments such as saris.
The use of certain sunscreens has already been discussed in the literature. US 4 788 054 (Bernhardt) teaches the use of N-phenylphthalisomides as ultraviolet radiation absorbers for cotton, wool, polyester and rayon. The compositions require an aqueous sulphuric acid vehicle for deposition. Fabric care compositions comprising a water dispersible / water soluble copolymers which prevent photofading are disclosed in EP 0 523 956 (Unilever).
US 5 474 691 (Severns) also discloses the use of a tumble drier sheet to transfer photofading inhibitors to fabrics.
None of these systems is suitable for delivering photofading inhibitors to the fabric surface during washing.
However the major problem that needs to be overcome is how to deposit photofading inhibitors onto fabric during the wash using a detergent containing washing system, which is designed to suspend particulate materials and solubilise oils.
The present invention addresses these problems, and relates to an improved method of depositing photofading inhibitors to fabrics during the washing process. In addition the present invention also relates to a method of improving the perfume delivery of compositions.
Thus according to one aspect of the invention there is provided a detergent composition comprising:
- i) a nonionic detergent surfactant;
- ii) a cationic quaternary ammonium compound material;
- iii) a liquid photofading inhibitor having a log P value of at least 1.9 or a solid photofading inhibitor dissolved in a liquid the liquid having a log P of at least 1.9 or mixtures thereof; and
- iv) optionally, an anionic surfactant;
The invention further relates to the use of a detergent composition as described above for the deposition of a photofading inhibitor onto a fabric.
Without being bound by theory it is thought that the extent of individual dye fading is dependent on the light wavelength. Some dyes are photodegraded primarily by the UV component of solar radiation, for other dyes the visible component of solar radiation is the main cause of colour loss, whilst others are equally affected by both visible and UV radiation. Thus, in order to minimise photofading across the mix of dyes encountered in the home, it is essential to protect articles from the whole solar spectrum.
Protection against solar radiation can be achieved with UVA and UVB absorbing materials with high extinction coefficients. These compounds are commonly called sunscreens. However, the use of such materials is preferably limited for protection against UV radiation with a wavelength of 400nm or below as compounds with the whole or part of their spectra above 400nm will be coloured.
Protection from visible radiation with a wavelength of 400nm or greater is preferably achieved by using singlet oxygen quenchers, free radical traps and anti-oxidants.
It is therefore advantageous to deliver to the fabric surface both UV sunscreens and materials that will protect dyes from visible radiation and thus mixtures of sunscreens and antioxidants, singlet oxygen quenchers or free radical traps are used..
If liquid, the photofading inhibitors must have a log P value of at least 1.9, more preferably of at least 2.5, most preferably greater than 3.5.
If solid the photofading inhibitor must be dispersed in a liquid, the liquid having a log P value of at least 1.9, more preferably of at least 2.5, most preferably greater than 3.5. It is also beneficial if the liquid in which the solid photofading inhibitor is to be dissolved is immiscible in water or only sparingly soluble. By sparingly soluble a solubility of no more than 0.04 moles/litre is meant.
Log P is the octanol/water partition coefficient and can be used to measure the hydrophobicity of a molecule. Log P is determined experimentally. The procedure is described in Chemical Reviews Volume 71, number 5, pages 52-5-616(1971).
It is preferred that the photofading inhibitor or photofading inhibitor mixture is present at levels from 0.01 wt% to 10 wt% of the total weight of the composition. The more preferred level of sunscreen is from 0.025 wt% to 2.5 wt%, and most preferably 0.05 wt% to 0.5 wt%.
In the context of this invention a sunscreen is described as any material which absorbs UVA or UVB radiation. It is advantageous if the sunscreens have a molar extinction coefficient (E) of greater than 2,000 mol-1 cm-1 .
The International Commission on Illumination (CIE)in 1970 defined the UV wavelength subdivisions as:-
The sunscreen can be an oily liquid with a logP of at least 1.9 or a solid organic material that can be dissolved in a water immiscible or sparingly water soluble liquid, the liquid having a logP of greater than 1.9.
Preferably the sunscreen absorbs light at a wavelength from about 280-400nm.
Suitable sunscreens are described in:
N.A. Saath, Cosmestics and Toiletries Vol 102 March 1987 page 21-39 Classifications given as table 2 on page 22,;
N.A. Saath, Evolution of modern sunscreen chemicals pages 3-35; Cosmetics and Toiletries Vol 107 March 1992. Sunscreen use in cosmetic formulas, pages 45-47; Ultra violet absorbers by S.B. Miller, G.R. Lappin, and C.E. Tholstrup in 1968-1969 Modern Plastics Encyclopedia, pages 442-447 and; G.R. Lappin, Encyclopedia of polymer science and technology, vol 14, pages 125-148, Ultra violet radiation absorbers.
Examples of typical sunscreens but not meant to be exclusive are:
- 2-Ethylhexyl-4-methoxy cinnamate (Parsol MCX)
- 2-Ethoxyethyl-4-methoxy cinnamate
- Propyl-4-methoxy cinnamate
- i-Amyl-4-methoxy cinnamate
- Cyclohexyl-4-methoxy cinnamate
- i-Propyl-4-methoxy cinnamate
- Octyl cinnamate
- Ethyl-4-iso-propyl cinnamate
- Ethyl-di-iso-propyl cinnamate and methyl ester
- Ethyl-a-cyano-b-phenyl cinnamate
- 2-Ethylhexyl-a-cyano-b-phenyl-cinnamate
- 2-Ethylhexyl salicylate (Sunarome WMO)
- 3,3,5-Trimethyl cyclohexyl-2-hydroxy benzoate
- 3,3,5-Trimethyl cyclohexyl-2-acetamido benzoate
- 2-Ethylhexyl-2-(4-phenylbenzoyl)benzoate
- 4-Isopropylbenzyl salicylate
- Amyl salicylate
- Menthyl salicylate
- Homomenthyl salicylate
- Phenyl salicylate
- Benzyl salicyclate
- i-Decyl salicylate
- Ethyl 4-bis(hydroxypropyl)amino benzoate (Amerscheen P)
- 2,3-Dihydroxypropyl-4-amino benzoate (Nipa GMPA)
- Menthyl-2-aminobenzoate (Sunarome UVA)
- 2-Ethylhexyl-4-dimethylamino benzoate (Escalol 507)
- Amyl-4-dimethylamino benzoate
- Ethyl-4-dimethylaminobenzoate
- Butyl-4-dimethylaminobenzoate
- 4-bis(polyethoxy)-4-aminobenzoic acid polyethoxyethyl ester (Uvinul P-25)
- N-propoxylated ethyl-4-amino benzoate
- 2-hydroxy-4-methoxy benzophenone (Uvinul M40)
- 2,2'-Dihydroxy-4-methoxybenzophenone (Spectra-Sorb UV-24)
- 2,4-Dihydroxybenzophenone (Uvinul 400)
- 2,2',4,4'-Tetrahydroxybenzophenone (Uvinul D-50)
- 2,2'-Dihydroxy-4,4'-dimethoxybenzophenone (Uvinul D-49)
- 2-Hydroxy-4-(2-ethylhexyloxy)benzophenone (Uvinul408)
- 2-Hydroxy-4-methoxy-4'-methylbenzophenone (Mexenone)
- 4-Phenyl-benzophenone
- 2-Ethylhexyl-4'-phenyl-benzophenone-2-carboxylate 2-Hydroxy-4-n-octoxybenzophenone
- 2-Hydroxy-3-carboxybenzophenone
- 2-Ethylhexyl-2-cyano-3,3'-diphenylacrylate (Uvinul N-539)
- Ethyl-2-cyano-3,3'-diphenylacrylate (Uvinul N-35)
- 3-Imidazol-4yl acrylic acid and ethyl ester
- 2-Cyano-3-(4-methoxyphenyl)acrylate and hexyl ester
- 1-(4-Isopropyl phenyl)-3-phenyl propan-1,3-dione (Eusolex 8020)
- 1-(4-t-Butylphenyl)-3-(4-methoxyphenyl)propan-1,3-dione
- 1,3-bis(4-Methoxyphenyl)propane-1,3-dione
- 3-(4-Methylbenzylidene)-bornan-2-one (Eusolex 6300)
- 5-(3,3-Dimethyl-2-norbonylidene)-3-penten-2-one
- 3-Benzylidene bornan-2-one
- Digalloyl trioleate
- 2-Hydroxy-1,4-naphthalenedione
- 5-Methyl-2-phenylbenzoxazole
- 2,4,6-Trianilino-4-(carbo-2'-ethylhexyl-1'-oxy)-1,3,5-triazine (Uvinul T-150)
- 2,2'-hydroxy-5-methylphenyl-benzotriazol
- 2,2'-hydroxy-5-t-octylphenyl-benzotriazol
- Dibenzaldehydeamine
- Dianisoyl methane
- Methyl eugenol
- 2-Amino-6-hydroxypurin
- N-(4-Ethoxycarbonylphenyl)-N'-methyl-N'-phenylformamidine (Givosorb UV1)
- N-(4-Ethoxycarbonylphenyl)-N'-ethyl-N'-phenylformamidine (Givosorb UV2)
- 2-(2H-benzotriazol-2-yl)-4-methylphenol (Tinuvin P)
- 2-(6-Chloro-2H-benzotriazol-2-yl)-4-methyl-6-t-butyl phenol (Tinuvin 326)
- 2-(6-Chloro-2H-benzotriazol-2-yl)-4,6-di-t-butyl phenol (Tinuvin 327)
- 2-(2H-benzotriazol-2-yl)-4,6-di-t-pentyl phenol (Tinuvin 328)
- 3-(4'-Methylbenzylidene)-Camphor
Preferred sunscreen compounds contain at least one chromophore selected from the following groups and mixtures thereof.
Wherein R1 and R2 is a hydrogen, methyl, ethyl, C1-C22 branched or straight chain alkyl group; and mixtures thereof, preferably a methyl group.
Preferably the sunscreen compound containing at least one chromophore is selected from the group consisting of phenylbenzotriazoles, esters of cinnamic acid, benzophenones, esters of para aminobenzoic acid, esters of salicylic acid, dibenzoyl methane and mixtures thereof.
Most preferably the sunscreen is selected from the following groups and mixtures thereof.
Where R4 is a hydrogen, a hydroxy group, a C1-C22 alkyl group, preferably a hydrogen or a hydroxy group and most preferably a hydroxy group.
Where R5 is is a hydrogen, a hydroxy group, a C1-C22 alkyl group, more preferably a C1-C8 alkyl group and most preferably a tertiary amyl group or tertiary butyl group.
Where R6 is is a hydrogen, a hydroxy group, a C1-C22 alkyl group, more preferably a C1-C8 alkyl group and most preferably a tertiary amyl group or tertiary butyl group.
An example where R4 is hydroxyl and R5 and R6 are tertiary amyl groups is the commercial sunscreen Tinuvin 328, and where R4 is hydroxyl and R5 and R6 are tertiary butyl groups is Tinuvin 327. Both these sunscreens are manufactured by Ciba.
Where R7 is a hydrogen, a hydroxy group, a methoxy group,C1-C22 alkyl group,and mixtures thereof.
Where R8 is a hydrogen, a hydroxy group,C1-C22 alkyl group,and mixtures thereof.
Where R9 is a hydrogen, a hydroxy group, C1-C22 alkyl group, and mixtures thereof.
Where R10 is a hydrogen, or a C1-C22 alkyl group.
Where R11 is a hydrogen, or a C1-C22 alkyl group.
Where R13 is a C1-C22 alkyl group.
Where R14 is a C1-C22 alkyl group
Where R15 is a hydrogen, methoxy or a C1-C22 alkyl group.
In the context of this invention the term antioxidant refers to a non-fabric staining, light stable antioxidant compound, that is either an oily liquid with a logP of at least 1.9 or a solid organic material that can be dissolved in a water immiscible or sparingly water soluble liquid with a logP of greater than 1.9.
Examples of anti-oxidants meeting these requirements can be found in Kirk-Othmer Encyclopaedia of Chemical Technology, fourth edition, volume 3, pages 424-447.
Examples of typical antioxidant compounds and/or singlet oxygen quenchers include :
ascorbic palmitate, butylated hydroxy anisole, tertiary butyl hydroquinone, natural tocopherols and derivatives such as vitamin E acetate and Irganox antioxidants as supplied by Ciba Geigy such as Irganox 1010 (tetrakis methylene (3,5-di-tert-butyl-4hydroxycinnamate)) methane), Irganox 1035 (thiodiethylene bis (3,5-di-tert-butyl-4-hydroxyhydrocinnamate)), Irganox 1076 (octadecyl propan-(3-benzene-3',5' di tert butyl-4' hydroxy)-oate, Irganox 1425 (calcium bis (monoethyl(3,5-di-tert-butyl-4-hydroxybenzyl) phosphonate), Irganox 3052 2-propanoic acid 2-(1,1-di-tertiary butyl)-6 -[3-(1,1di-tertiary butyl)-2-hydroxy-5-methylphenyl]-4-methylphenyl ester, Irganox 3114 (1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-s-triazine-2,4,6-(1H, 3H, 5H)trione Irganox 3125 3,5-di-tert-butyl-4-hydroxyhydrocinnamic triester with 1,3,5,-tris(2-hydroxyethyl)-s_triazine-2,4,6-(1H, 3H, 5H)-trione), Irganox 1098 (N,N'-hexamethylene bis(3,5-di-tert-butyl-4hydroxyhydrocinnamamide), Diazobicyclo[2,2,2]octane (DABCO) and mixtures thereof.
Preferred materials include
The composition of the invention requires the presence of a nonionic surfactant.
Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, especially the C8-C20 aliphatic alcohols ethoxylated with an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more especially the C10-C15 primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol. Non-ethoxylated nonionic surfactants include alkylpolyglycosides, glycerol monoethers, and polyhydroxyamides (glucamide).
It is preferred if the level of nonionic surfactant is from 2 wt% to 40 wt%, preferably from 10 wt% to 30 wt% of the total product.
The choice of detergent-active compound (surfactant), and the amount present, will depend on the intended use of the detergent composition. In fabric washing compositions, different surfactant systems may be chosen, as is well known to the skilled formulator, for handwashing products and for products intended for use in different types of washing machine.
Although an anionic surfactant may be present in compositions of the invention it is preferred if it is absent.
If present it is preferred if the ratio of cationic material to anionic material is at least 2:1.
If present suitable anionic surfactants are well-known to those skilled in the art and include alkylbenzene sulphonate primary and secondary alkyl sulphates, particularly C8-C15 primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates; ethercarboxylates; isothionates; sarcosinates and fatty acid ester sulphonates, Sodium salts are generally preferred.
Detergent compositions suitable for use in most automatic fabric washing machines generally contain anionic non-soap surfactant, or nonionic surfactant, or combinations of the two in any ratio, optionally together with soap.
For compositions in solid form, especially powder, the detergent surfactant is advantageously solid at room temperature as this provides crisp composition particles.
The compositions of the invention must contain a quaternary ammonium compound cationic compound.
It is advantageous if the quaternary ammonium compound is a quaternary ammonium compound having at least one C12-C22 alkyl chain.
It is preferred if the quaternary ammonium compound has the following formula:
A second class of materials for use with the present invention are the quaternary ammonium compound having the following formula:
Other suitable quaternary ammonium compounds are disclosed in EP 0 239 910 (Procter and Gamble).
It is preferred if the ratio of cationic to nonionic surfactant is from 1:100 to 50:50, more preferably 1:50 to 20:50.
The cationic compound may be present from 0.02 wt% to 20 wt% of the total weight of the composition.
Preferably the cationic compound may be present from 0.05 wt% to 15 wt%, a more preferred composition range is from 0.2 wt% to 5 wt%, and most preferably the composition range is from 0.4 wt% to 2.5 wt% of the total weight of the composition.
If the product is a liquid it is preferred if the level of cationic surfactant is from 0.05wt% to 10wt% of the total weight of the composition. Preferably the cationic compound may be present from 0.2wt% to 5 wt%, and most preferably from 0.4 wt% to 2.5 wt% of the total weight of the composition.
If the product is a solid it is preferred if the level of cationic surfactant is 0.05 wt% to 15 wt% of the total weight of the composition. A more preferred composition range is from 0.2 wt% to 10 wt%, and the most preferred composition range is from 0.9 wt% to 3.0 wt% of the total weight of the composition.
The detergent compositions of the invention will generally also contain one or more detergency builders. The total amount of detergency builder in the compositions will suitably range from 5 to 80 wt%, preferably from 10 to 60 wt%.
Inorganic builders that may be present include sodium carbonate, if desired in combination with a crystallisation seed for calcium carbonate, as disclosed in GB 1 437 950 (Unilever); crystalline and amorphous aluminosilicates, for example, zeolites as disclosed in GB 1 473 201 (Henkel), amorphous aluminosilicates as disclosed in GB 1 473 202 (Henkel) and mixed crystalline/amorphous aluminosilicates as disclosed in GB 1 470 250 (Procter & Gamble); and layered silicates as disclosed in EP 164 514B (Hoechst). Inorganic phosphate builders, for example, sodium orthophosphate, pyrophosphate and tripolyphosphate are also suitable for use with this invention.
The detergent compositions of the invention preferably contain an alkali metal, preferably sodium, aluminosilicate builder. Sodium aluminosilicates may generally be incorporated in amounts of from 10 to 70% by weight (anhydrous basis), preferably from 25 to 50 wt%.
The alkali metal aluminosilicate may be either crystalline or amorphous or mixtures thereof, having the general formula:
0.8-1.5 Na2O. Al2O3. 0.8-6 SiO2
These materials contain some bound water and are required to have a calcium ion exchange capacity of at least 50 mg CaO/g. The preferred sodium aluminosilicates contain 1.5-3.5 SiO2 units (in the formula above). Both the amorphous and the crystalline materials can be prepared readily by reaction between sodium silicate and sodium aluminate, as amply described in the literature.
Suitable crystalline sodium aluminosilicate ion-exchange detergency builders are described, for example, in GB 1 429 143 (Procter & Gamble). The preferred sodium aluminosilicates of this type are the well-known commercially available zeolites A and X, and mixtures thereof.
The zeolite may be the commercially available zeolite 4A now widely used in laundry detergent powders. However, according to a preferred embodiment of the invention, the zeolite builder incorporated in the compositions of the invention is maximum aluminium zeolite P (zeolite MAP) as described and claimed in EP 384 070A (Unilever). Zeolite MAP is defined as an alkali metal aluminosilicate of the zeolite P type having a silicon to aluminium ratio not exceeding 1.33, preferably within the range of from 0.90 to 1.33, and more preferably within the range of from 0.90 to 1.20.
Especially preferred is zeolite MAP having a silicon to aluminium ratio not exceeding 1.07, more preferably about 1.00. The calcium binding capacity of zeolite MAP is generally at least 150 mg CaO per g of anhydrous material.
Organic builders that may be present include polycarboxylate polymers such as polyacrylates, acrylic/maleic copolymers, and acrylic phosphinates; monomeric polycarboxylates such as citrates, gluconates, oxydisuccinates, glycerol mono-, di- and trisuccinates, carboxymethyloxysuccinates, carboxymethyloxymalonates, dipicolinates, hydroxyethyliminodiacetates, alkyl- and alkenylmalonates and succinates; and sulphonated fatty acid salts. This list is not intended to be exhaustive.
Especially preferred organic builders are citrates, suitably used in amounts of from 5 to 30 wt%, preferably from 10 to 25 wt%; and acrylic polymers, more especially acrylic/maleic copolymers, suitably used in amounts of from 0.5 to 15 wt%, preferably from 1 to 10 wt%.
Builders, both inorganic and organic, are preferably present in alkali metal salt, especially sodium salt, form.
Detergent compositions according to the invention may also suitably contain a bleach system. Fabric washing compositions may desirably contain peroxy bleach compounds, for example, inorganic persalts or organic peroxyacids, capable of yielding hydrogen peroxide in aqueous solution.
Suitable peroxy bleach compounds include organic peroxides such as urea peroxide, and inorganic persalts such as the alkali metal perborates, percarbonates, perphosphates, persilicates and persulphates. Preferred inorganic persalts are sodium perborate monohydrate and tetrahydrate, and sodium percarbonate.
Especially preferred is sodium percarbonate having a protective coating against destabilisation by moisture. Sodium percarbonate having a protective coating comprising sodium metaborate and sodium silicate is disclosed in GB 2 123 044B (Kao).
The peroxy bleach compound is suitably present in an amount of from 0.1 to 35 wt%, preferably from 0.5 to 25 wt%.
The peroxy bleach compound may be used in conjunction with a bleach activator (bleach precursor) to improve bleaching action at low wash temperatures. The bleach precursor is suitably present in an amount of from 0.1 to 8 wt%, preferably from 0.5 to 5 wt%.
Preferred bleach precursors are peroxycarboxylic acid precursors, more especially peracetic acid precursors and pernoanoic acid precursors. Especially preferred bleach precursors suitable for use in the present invention are N,N,N',N'-tetracetyl ethylenediamine (TAED) and sodium noanoyloxybenzene sulphonate (SNOBS). The novel quaternary ammonium and phosphonium bleach precursors disclosed in US 4 751 015 and US 4 818 426 (Lever Brothers Company) and EP 402 971A(Unilever), and the cationic bleach precursors disclosed in EP 284 292A and EP 303 520A (Kao) are also of interest.
The bleach system can be either supplemented with or replaced by a peroxyacid. Examples of such peracids can be found in US 4 686 063 and US 5 397 501 (patent on TPCAP - Unilever). A preferred example is the imido peroxycarboxylic class of peracids described in EP A 325 288, EP A 349 940, DE 382 3172 and EP 325 289. A particularly preferred example is phtalimido peroxy caproic acid (PAP). Such peracids are suitably present at 0.1 - 12%, preferably 0.5 - 10%.
A bleach stabiliser (heavy metal sequestrant) may also be present. Suitable bleach stabilisers include ethylenediamine tetraacetate (EDTA), the polyphosphonates such as Dequest (Trade Mark) and non-phosphate stabilisers such as EDDS (ethylene diamine di-succinic acid). These Bleach stabilisers are also useful for stain removal, especially in products containing low levels of bleaching species or no bleaching species.
An especially preferred bleach system comprises a peroxy bleach compound (preferably sodium percarbonate optionally together with a bleach activator), and a transition metal bleach catalyst as described and claimed in EP 458 397A, EP 458 398A and EP 509 787A (Unilever).
Suitable enzymes include the proteases, amylases, cellulases, oxidases, peroxidases and lipases usable for incorporation in detergent compositions.
Preferred proteolytic enzymes (proteases) are, catalytically active protein materials which degrade or alter protein types of stains when present as in fabric stains in a hydrolysis reaction. They may be of any suitable origin, such as vegetable, animal, bacterial or yeast origin.
Proteolytic enzymes or proteases of various qualities and origins and having activity in various pH ranges of from 4-12 are available and can be used in the instant invention. Examples of suitable proteolytic enzymes are the subtilisins, which are obtained from particular strains of B. subtilis and B. licheniformis, such as the commercially available subtilisins Maxatase (Trade Mark), as supplied by Gist-Brocades N.V., Delft, Holland, and Alcalase (Trade Mark), as supplied by Novo Industri A/S, Copenhagen, Denmark.
Particularly suitable is a protease obtained from a strain of Bacillus having maximum activity throughout the pH range of 8-12, being commercially available, e.g. from Novo Industri A/S under the registered trade-names Esperase (Trade Mark) and Savinase (Trade-Mark). The preparation of these and analogous enzymes is described in GB 1 243 785. Other commercial proteases are Kazusase (Trade Mark) (obtainable from Showa-Denko of Japan), Optimase (Trade Mark) (from Miles Kali-Chemie, Hannover, West Germany), and Superase (Trade Mark) (obtainable from Pfizer of U.S.A.).
Detergency enzymes are commonly employed in granular form in amounts of from about 0.1 to about 3.0 wt%.
Any perfume is suitable for use with the present invention. However we have found that the presence of a photofading inhibitor aids the deposition of perfume, this affect is especially pronounced with non-volatile perfume ingredients. The converse of this is also true, in that the presence of perfume aids the deposition of the photofading inhibitor.
The compositions of the invention may contain alkali metal, preferably sodium carbonate, in order to increase detergency and ease processing. Sodium carbonate may suitably be present in amounts ranging from 1 to 60 wt%, preferably from 2 to 40 wt%. However, compositions containing little or no sodium carbonate are also within the scope of the invention.
Powder flow may be improved by the incorporation of a small amount of a powder structurant, for example, a fatty acid (or fatty acid soap), a sugar, an acrylate or acrylate/maleate polymer, or sodium silicate.
One preferred powder structurant is fatty acid soap, suitably present in an amount of from 1 to 5 wt%.
Other materials that may be present in detergent compositions of the invention include sodium silicate; antiredeposition agents such as cellulosic polymers; inorganic salts such as sodium sulphate; lather control agents or lather boosters as appropriate; proteolytic and lipolytic enzymes; dyes; coloured speckles; foam controllers; fabric softening compounds, soil release polymers, fluorescers and decoupling polymers. This list is not intended to be exhaustive.
The detergent composition when diluted in the wash liquor (during a typical wash cycle) will give a pH of the wash liquor from 7 to 10.5.
The detergent components of the present invention may be incorporated in detergent compositions of all physical types, for example, powders, liquids, gels and solid bars.
Detergent compositions of the invention may be prepared by any suitable method.
Particulate detergent compositions are suitably prepared by spray-drying a slurry of compatible heat-insensitive ingredients, and then spraying on or postdosing those ingredients unsuitable for processing via the slurry. The skilled detergent formulator will have no difficulty in deciding which ingredients should be included in the slurry and which should not.
Particulate detergent compositions of the invention preferably have a bulk density of at least 400 g/l, more preferably at least 500 g/l.
Especially preferred compositions have bulk densities of at least 650 g/litre, more preferably at least 700 g/litre.
Such powders may be prepared either by post-tower densification of spray-dried powder, or by wholly non-tower methods such as dry mixing and granulation; in both cases a high-speed mixer/granulator may advantageously be used.
Processes using high-speed mixer/granulators are disclosed, for example, in EP 340 013A, EP 367 339A, EP 390 251A and EP 420 317A (Unilever).
Liquid detergent compositions can be prepared by admixing the essential and optional ingredients thereof in any desired order to provide compositions containing components in the requisite concentrations. Liquid compositions according to the present invention can also be in compact form which means it will contain a lower level of water compared to a conventional liquid detergent.
The invention will now be illustrated with reference to the following non-limiting Examples.
Comparative examples are illustrated by a letter and examples of the invention are illustrated by a number.
Five sequential washes were carried out in a Tergotometer under the following conditions.
Washes with systems were carried out in distilled water at a total surfactant concentration of 1 g/l.
Fabrics were removed at the end of each wash, and the liquor volume for subsequent washes adjusted to 30:1
The Parsol MCX present on the dry fabric was recovered by solvent extraction. A 3g piece of knitted cotton was placed in a 20 ml screw top vial, and 15 ml of high purity isopropyl alcohol added. The vial was roller mixed for 3 hours on a Luckham Multimix Major, before sonicating for 30 minutes in a small sonic bath. The concentration of Parsol MCX present in the extract was then determined by GC/MS analysis (Finnigan Magnum fitted with a 25 metre SGE BPX-5 (non-polar) glass capillary column of internal diameter 0.22mm with a film thickness of 0.25µm). UV/visible absorbance procedures were also employed as a check of sunscreen deposition level. A Perkin Elmer λ2 spectrometer was used to measure the absorbance of the isopropyl alcohol extract solutions at the λmax of the sunscreen. The amount of sunscreen deposited was determined using a calibration plot obtained from measurement of the absorbance of standard sunscreen solutions.
Parsol MCX is 2-Ethylhexyl 4-methoxycinnamate with a log P value of 5.2.
The results show better deposition when the nonionic/cationic ratio of the invention is used.
Table 6 shows the comparison of perfume components delivered to cotton fabric from a CTAB/nonionic (10/90) liquid product containing 17% total active. The perfume components are quoted as concentration (ppm) in a solvent extract from the washed and dried fabric.
Two products were compared, one containing 0.5% perfume , the other containing 0.5% and 0.1% Parsol MCX. The perfume has twenty components, each component of the perfume being present at equal concentration.
Table 6 shows the level of perfume deposited onto fabric.
Two non-ionic cationic liquids were prepared containing the solid sunscreen Tinuvin 328 (2-(2-hydroxy-3,5-di-tertiaryamyl-phenyl)-2H-benzotriazole ex Ciba Geigy). Examples 4 and E are listed in Table 7. The only difference between the two formulations is the solvent used to dissolve the Tinuvin 328 sunscreen. Example 4 contains diethylphthalate which has a logP of 2.15, and Example E contains 2-butoxyethanol which is water soluble and has a logP of 0.84.
Washes were carried out in a Tergotometer at 20°C using 6g/l of each product over a period of 20 minutes in the presence of 1.14g/l of borax buffer. An initial liquor volume of 1200ml was selected for the first wash. Fabrics were removed after each wash to determine the level of sunscreen deposited on the fabric. The wash liquor volume was reduced in the second and third washes to maintain the liquor to cloth ratio at 30:1. At the end of each wash the fabrics were squeezed to remove excess liquor and rinsed three times at a liquor to cloth ratio of 40:1, before air drying in the dark. Dry white cotton pieces measuring 5.08 cm x 11.43 cm (2" x 4.5") taken from each wash were each placed in a glass sample vial and 15ml of ethylacetate added. The vials were rolled on a roller mixer (Luckham Multimix Major) for a minimum period of 2 hours. The optical density of the extracts were then measured at 303nm, the λmax of Tinuvin 328. The results in table 8 show that delivery of Tinuvin 328 to cotton was achieved in the presence of diethyl phthalate. Whereas in the presence of 2-butoxyethanol readings were close to those obtained with a sunscreen free control.