WO1994011485A1

WO1994011485A1 - Liquid detergent compositions

Info

Publication number: WO1994011485A1
Application number: PCT/EP1993/003011
Authority: WO
Inventors: Anthony Henry Clements
Original assignee: Unilever N.V.; Unilever Plc
Priority date: 1992-11-17
Filing date: 1993-10-28
Publication date: 1994-05-26
Also published as: GB9224052D0; EP0670882A1; AU5372494A

Abstract

Non-aqueous liquid detergent composition comprising a surfactant, a builder and a fluorescent whitening agent are disclosed, wherein said fluorescent whitening agent is a dibenzofuran-diphenyl compound of formula (I), wherein R1 is a C¿1?-C4 alkyl or a phenyl group; R is hydrogen, a C1-C4 alkyl or alkoxy group, or phenoxy group; and M is hydrogen and/or a non-chromophoric cation.

Description

LIQUID DETERGENT COMPOSITIONS

This invention relates to non-aqueous liquid detergent compositions, comprising a fluorescent whitening agent. The term "non-aqueous" used herein refers to liquids containing little or no water as opposed to the term "aqueous" which refers to liquids containing relatively high proportions of water in the liquid phase. The term "liquid" used herein encompasses the meaning of liquid in its broadest sense and includes not only the low viscosity to highly viscous pourable liquids but also paste-like and gel-type products.

Non-aqueous liquid detergent compositions are known in the art and have been described in quite a number of patent publications for use in the washing of fabrics and other substrates. They normally comprise a non-aqueous liquid phase having incorporated therein as dispersion, solution or combination thereof, the usual detergent components and adjuncts depending on the purpose of use, primarily surfactants and builders. The liquid phase often comprises a nonionic surfactant as major component, which apart from acting as carrier liquid for the detergent components usually and preferably also has detergent-active properties, thereby acting wholly or in part as a surfactant ingredient.

Liquid compositions offer several advantages over solid compositions. For example, liquid compositions are easier to measure, to dispense and to dissolve into a laundering liquor. Furthermore liquid compositions give more confidence to the consumer of being safer and less harsh to the washed or laundered textile than solid compositions.

This may be the reasons why heavy duty and light duty built laundry liquid detergent products are gaining in popularity ever since their introduction on the market at the expense of powdered detergent products. An advantage of formulating non-aqueous liquids over aqueous liquids is that in them the solubility of the bleach as well as that of other water-soluble components commonly included in detergent compositions, and with which the bleach may otherwise react in an undesired manner, is extremely low. A further advantage of non-aqueous liquids is that they provide a way of concentrating liquid detergents without giving in on washing performance.

In the application of fabric washing, a fluorescent whitening agent is normally incorporated to provide an optical brightening or whitening effect on the washed fabrics. This effect is of foremost importance for whites, but is often less desirable for coloureds, because of the more or less shade-change resulting therefrom.

It is therefore an object of the present invention to provide a non-aqueous liquid detergent composition containing a fluorescent whitening agent which is suitable not only for washing white fabrics but also for washing coloured fabrics without substantially affecting the shade.

It has now been found that this object can be achieved by using a fluorescent whitening agent of the formula:

wherein R¹ is a C₁-C₄ alkyl or a phenyl group; R is hydrogen, a C^-^ alkyl or alkoxy group, or a phenoxy group; and M is hydrogen and/or a non-chromophoric cation.

Accordingly the invention provides a non-aqueous liquid detergent composition comprising a surfactant, a builder and a fluorescent whitening agent, characterized in that the fluorescent whitening agent is a di-benzofurandiphenyl compound of the formula (I) , wherein R¹ is a C-^^ alkyl or a phenyl group; R is hydrogen, a C_j-^ alkyl or alkoxy group, or a phenoxy group; and M is hydrogen and/or a non-chromophoric cation.

Preferred compounds are those wherein R¹ is a C*_|_-C₄ alkyl, particularly methyl, and wherein R is hydrogen or Cy- -C^ alkyl (especially methyl) . It is further preferable that if R is a C -C^ alkyl, e.g. methyl, it is bound on the aromatic ring in ortho-position the sulphonate group and para to the furan oxygen. The cation M is preferably an alkalimetal cation, particularly Na or K.

Hence the following specific compounds are particularly preferred fluorescent whitening agents for use in the present invention:

A yellowish crystalline powder. UV-Absorption: λ max. = 351 mm; G •= 74450 (in DMF/H₂0 1:1)

A yellowish crystalline powder. UV Absorption: λ max. 353 mm; t = 76300 (in D F/H₂0 1:1) . These fluorescent whitening agents are known and described in EP-A-0, 395,588. Upon examination it was found that these di-benzofurandiphenyl fluorescers when used in a non- aqueous liquid detergent base composition show excellent whitening performance at higher temperatures of 60°C and above, but significantly lower performance at the lower temperature region of below 60°C, especially between 20° and 40°C.

In view of this temperature dependency of performance the present fluorescent whitening agents are extremely suitable for use in non-aqueous liquid detergent compositions, that will give excellent fluorescence whitening at temperatures of from 60°C, and above, but only weak fluorescence whitening at temperatures below 60°C, especially between 20° and 40°C.

Since whites are or can be normally washed at higher temperatures and (fine) coloureds are normally washed at lower temperatures, the inventive liquid detergent compositions will give satisfactory whitening at temperatures of 60°C and above for washing white or paramount white fabrics, but will give less shade-change when washing coloured fabrics at temperatures below 60°C, especially between 20° and 40°C.

Non-aqueous liquid detergent compositions are described for example in US-A-4, 316,812; US-A-4,874,537 and EP-A- 0,484,095. Any of these liquid detergent compositions can be used as basis for incorporating the fluorescent whitening agent according to the invention. The lack of water in such products would enable more easily the incorporation therein of unstable or incompatible but often desirable ingredients, such as bleaches, enzymes and the like, although the present invention is applicable even to products which do not contain such ingredients. The free water content of non-aqueous liquid detergent products is generally less than 5% by weight, preferably less than 2% by weight, more preferably substantially nil. The compositions may be isotropic (free of dispersed solids) or may comprise a liquid phase in combination with a solid phase (e.g. builders, bleaches, abrasives and enzymes) dispersed therein. In that case the liquid phase may preferably constitute from 10 to 100% by weight, more preferably 20-80% and most preferably from 30-60% by weight of the composition. The solid phase preferably constitutes from 0-90% by weight, more preferably 20-80%, most preferably from 40-70% by weight of the composition.

As explained hereinbefore the liquid phase of non-aqueous liquid detergent compositions often and preferably comprises a liquid nonionic surfactant as major component.

Nonionic detergent surfactants are well-known in the art. They normally consist of a water-solubilizing polyalkoxylene or a mono- or di-alkanolamide group in chemical combination with an organic hydrophobic group derived, for example, from alkylphenols in which the alkyl group contains from about 6 to about 12 carbon atoms, dialkylphenols in which each alkyl group contains from 6 to 12 carbon atoms, primary, secondary or tertiary aliphatic alcohols (or alkyl-capped derivatives thereof) , preferably having from 8 to 20 carbon atoms, monocarboxylic acids having from 10 to about 24 carbon atoms in the alkyl group and polyoxypropylenes. Also common are fatty acid mono- and dialkanolamides in which the alkyl group of the fatty acid radical contains from 10 to about 20 carbon atoms and the alkyloyl group having from 1 to 3 carbon atoms. In any of the mono- and di- alkanolamide derivatives, optionally, there may be a polyoxyalkylene moiety joining the latter groups and the hydrophobic part of the molecule. In all polyakoxylene containing surfactants, the polyalkoxylene moiety preferably consists of from 2 to 20 groups of ethylene oxide or of ethylene oxide and propylene oxide groups. Amongst the latter class, particularly preferred are those described in EP-A-225, 654 , especially for use as all or part of the liquid phase. Also preferred are those ethoxylated nonionics which are the condensation products of fatty alcohols with from 9 to 15 carbon atoms condensed with from 3 to 11 moles of ethylene oxide. Examples of these are the condensation products of C₁₁_₁₃ alcohols with (say) 3 or 7 moles of ethylene oxide. These may be used as the sole nonionic surfactants or in combination with those as described in the last-mentioned European specification, especially as all or part of the liquid phase.

Another class of suitable nonionics comprise the alkyl polysaccharides (polyglycosides/oligosaccharides) such as described in any of specifications US 3,640,998; US 3,346,558; US 4,223,129; EP-A-92,355; EP-A-99,183; EP 70,074, '75, '76, ^»77; EP 75,994, ^»95, '96.

Mixtures of different nonionic detergent surfactants may also be used. Mixtures of nonionic detergent surfactants with other detergent surfactants such as anionic, cationic or ampholytic detergent surfactants and soaps may also be used.

Preferably the level of nonionic surfactants is from 10-90% by weight of the composition, more preferably from 20-70%, most preferably from 35 to 50%.

Examples of other liquid materials which may be present in the liquid phase are liquid bleach precursors such as for example glyceroltriacetate and solvent materials for example dodecanol. The level of liquid bleach precursors is preferably 0-20% by weight, more preferably 1-25%, most preferably 2-10%. The level of solvents other than nonionic surfactants is preferably from 0-20%, most preferably 0- 15%, more preferably 0-10% by weight. Preferably the solid phase -if any- comprises one or more ingredients selected from bleach materials, solid bleach activators, builders, deflocculants and minor ingredients such as fluorescers, enzymes and colouring agents. The solid phase should be in particulate form and preferably have a weight average particle size of less than 300 microns, more preferably less than 100 microns, especially less than 10 microns. The particle size may even be of sub- micron size. The proper particle size can be obtained by using materials of the appropriate size or by milling the total product in a suitable milling apparatus, e.g. a ball- mill and/or a colloid mill.

Bleaches include the halogen, particularly chlorine bleaches such as are provided in the form of alkalimetal hypohalites, e.g. hypochlorites. In the application of fabrics washing, the oxygen bleaches are preferred, for example in the form of an inorganic persalt, preferably with a bleach precursor or as a peroxy acid compound.

In the case of the inorganic persalt bleaches, the bleach precursor or activator makes the bleaching more effective at lower temperatures, i.e. in the range from ambient temperature to about 60°C, so that such bleach systems are commonly known as low-temperature bleach systems and are well-known in the art. The inorganic persalt such as sodium perborate, both the monohydrate and the tetrahydrate, acts to release active oxygen in solution, and the activator is usually an organic compound having one or more reactive acyl residues, which cause the formation of peroxy acids, the latter providing for a more effective bleaching action at lower temperatures than the peroxybleach compound alone. The ratio by weight of the peroxybleach compound to the activator is from about 20:1 to about 1:1, preferably from about 10:1 to about 1.5:1. The preferred level of the peroxybleach compound in the composition is from 0-30% by weight, more preferably 2-20%, most preferably 4-15%, while the preferred level of the activator is from 0-20% by weight, more preferably 1-10%, most preferably 2-8%.

Typical examples of the suitable peroxybleach compounds are alkalimetal perborates, both tetrahydrates and monohydrates, alkali metal percarbonates, persilicates and perphosphates, of which sodium perborate and sodium percarbonate are preferred. A commonly used bleach activator is TAED.

Another preferred class of bleach activators is that of hydrophobic peroxy acid bleach precursors, such as sodium nonanoyloxy benzene sulphonate and sodium -3,5,5- trimethyl hexanoyloxy benzene sulphonate. These activators are deemed to cause less (local) dye damage.

In certain cases and for particular reasons it may be desirable to also include a bleach catalyst, such as a transition metal compound or complex and the sulphonimines as described in US Patents 5,041,232 and 5,047,163, which may be used instead of or together with said bleach activators. A specifically preferred bleach catalyst for use herein is a manganese complex of formula [Mn^IV ₂(μ-0)₃(Me-MeTACN)₂] (PF₆)₂ as described in EP-A-0,458,397 and EP-A-0,458,398. Another preferred bleach catalyst is a manganese complex as described in our co- pending GB patent application 9127060.3. Alternatively the ligand and a manganese source can be separately added such as is described in co-pending GB application 9204706.7.

It may be desirable to include in the compositions, a stabiliser for the bleach or bleach system, for example hydroxyethylidene-l, 1-diphosphonic acid, ethylene diamine tetramethylene phosphonate and diethylene triamine pentamethylene phosphonate or other appropriate organic phosphonate or salt thereof, such as the Dequest^® range hereinbefore described. These stabilisers can be used in acid or salt form, such as the calcium, magnesium, zinc or aluminium salt form. The stabiliser may be present at a level of up to about 1% by weight, preferably between about 0.1% and about 0.5% by weight.

Deterqencv builders

The detergency builders are those materials which counteract the effects of calcium, or other ion, water hardness, either by precipitation or by an ion sequestering effect. They comprise both inorganic and organic builders. They may also be sub-divided into the phosphorus-containing and non-phosphorus types, the latter being preferred when environmental considerations are important.

In general, the inorganic builders comprise the various phosphate-, carbonate-, silicate-, borate- and aluminosilicates-type materials, particularly the alkali¬ metal salt forms. Mixtures of these may also be used.

Examples of phosphorus-containing inorganic builders, when present, include the water-soluble salts, especially alkali metal pyrophosphates, orthophosphates, polyphosphates and phosphonates. Specific examples of inorganic phosphate builders include sodium and potassium tripolyphosphates, phosphates and hexametaphosphates.

Examples of non-phosphorus-containing inorganic builders, when present, include water-soluble alkali metal carbonates, bicarbonates, borates, silicates, metasilicates, and crystalline and amorphous aluminosilicates. Specific examples include sodium carbonate (with or without calcite seeds) , potassium carbonate, sodium and potassium bicarbonates, silicates such as sodiummetasilicate and zeolites.

Examples of organic builders include the alkali metal, ammonium and substituted ammonium, citrates, succinates, malonates, fatty acid sulphonates, carboxymethoxy succinates, ammonium polyacetates, carboxylates, polycarboxylates, a inopolycarboxylates, polyacetyl carboxylates and polyhydroxysulphonates. Specific examples include sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid, nitrilotriacetic acid, oxydisuccinic acid, melitic acid, benzene polycarboxylic acids and citric acid. Other examples are organic phosphonate type sequestering agents such as those sold by Monsanto under the tradename of the Dequest range and alkanehydroxy phosphonates.

Other suitable organic builders include the higher molecular weight polymers and co-polymers known to have builder properties, for example appropriate polyacrylic acid, polymaleic acid and polyacrylic/polymaleic acid co- polymers and their salts, such as those sold by BASF under the Sokalan^® Trade Mark. Polyacrylates or their derivatives may also be useful for their antiashing properties.

Preferably the level of builder materials is from 5-50% by weight of the composition, more preferably 10-40%, most preferably 15-35%.

Surfactants While nonionic surfactants are quite effective at oily and greasy soil removal (e.g. sebum) , particulate soils, such as clay soils and the like, may be more effectively removed by anionic surfactants. Thus within the ambit of the present invention, a very wide variation in surfactant types and levels is possible. The selection of surfactant types and their proportions will be fully within the capability of those skilled in the art.

Useful composition within the invention will normally comprise blends of different surfactant types. Typical blends include those where the primary surfactants comprise a nonionic and/or non-alkoxylated anionic and/or alkoxylated anionic surfactant. Cationic, zwitterionic and amphoteric surfactants may also be present usually in minor amounts as desirable. These and other surfactants are described in "Surface Active Agents" Vol. I, by Schwartz & Perry, Interscience 1949; "Surface Active Agents" Vol. II, by Schwartz, Perry & Berch, Interscience 1958; the current editions of "McCutcheon's Emulsifiers & Detergents" published by the McCutcheon Manufacturing Confectioners Company; in "Tensid-Taschenbuch", H. Stache, 2nd Edition, Carl Hanser Verlag, Mϋnchen & Wien, 1981; and in the various patent literature describing various types of non- aqueous liquid detergent compositions, which for the purpose of the invention need no further detailing.

Other optional ingredients

Other ingredients comprise those remaining ingredients which may be used in liquid cleaning products, such as fabric conditioning agents, enzymes, perfumes (including deoperfumes) , micro-bicides, colouring agents, soil- suspending agents (anti-redeposition agent) , corrosion inhibitors, enzyme stabilising agents, and lather depressants.

Amongst the fabric conditioning agents which may be used, either in fabric washing liquids or in rinse conditioners, are fabric softening materials such as fabric softening clays, quaternary ammonium salts, imidazolinium salts, fatty amines and cellulases.

Enzymes which can be used in liquids according to the present invention include proteolytic enzymes, amylolytic enzymes and lipolytic enzymes (lipases) . Various types of proteolytic enzymes and amylolytic enzymes are known in the art and are commercially available. They may be incorporated as "prills", "maru es" or suspensions e.g.. Preferably enzymes are added as suspensions in a non- aqueous liquid surfactant. The preferred level of enzyme materials is from 0.01 to 10% by weight of the composition.

When it is desired to include anti-redepostion agents in the liquid cleaning products, the amount thereof is normally from about 0.1% to about 5% by weight, preferably from about 0.2% to about 2.5% by weight of the total liquid composition. Preferred anti-redeposition agents include carboxy derivatives of sugars and celluloses, e.g. sodium carboxymethyl cellulose, anionic poly-electrolytes, especially polymeric aliphatic carboxylates, or organic phosphonates.

The dibenzofuran diphenyl fluorescent whitening agent in the non-aqueous liquid detergent composition of the invention may be used in the acid form or preferably in the form of its alkalimetal salt, for example the sodium salt, in amounts of from about 0.02 to 1.0% by weight, preferably from 0.03 to 0.8% by weight, and typically from 0.05 to 0.25% by weight. Although it is preferred to use the present fluorescent agent alone, the use thereof in admixture with other types of fluorescent agents is not excluded and is within the ambit of the present invention.

Good stability against strong oxidizing and bleaching agents is an additional advantage of this dibenzofuran diphenyl fluorescent whitening agent, which makes it very suitable too for use in non-aqueous liquid detergent compositions containing a persalt or a persalt and a bleach precursor as the bleach system or a peroxyacid such as 1,12 diperoxydodecane dioic acid (DPDA) and phthaloyla ido percaproic acid (PAP) , with or without a bleach catalyst.

Accordingly in one preferred embodiment the non-aqueous liquid detergent composition of the invention comprises a persalt and a bleach precursor as the bleach system or a peroxyacid compound. In another preferred embodiment the composition of the invention comprises an oxygen bleach and a manganese bleach catalyst as described hereinbefore.

A further additional advantage of the dibenzofurandiphenyl fluorescent whitening agent is its excellent light stability, which makes it possible for liquid detergent compositions comprising the instant FWA to be packed in attractive clear transparent or translucent containers, e.g. bottles.

Accordingly in another aspect the invention provides a liquid detergent composition comprising a surfactant, a builder and the dibenzofurandiphenyl fluorescent whitening agent as hereinbefore described, packed in transparent or translucent containers, preferably bottles.

The invention will now be further illustrated by way of the following non-limiting examples.

Example I

The influence of temperature (X-axis; in °C) on fluorescent brightening (Y-axis; in Delta F (460-460*)) from a non- aqueous liquid detergent composition (NAL) containing sodium perborate and TAED (N, N, N¹, N¹-tetraacetyl ethylene diamine) and different types of fluorescent whitening agent is shown in Figure 1.

NAL-base com osition nominal

Sipernat D 17³⁾ 3

Silicone DB100 (antifoa ) 1.2

Enzymes (Savinase/Lipolase) 0.8

Fluorescent whitening agent⁴-¹ 0.1 (at EJ 1100) Perfume balance

1) - Narrow range ethoxylate Novel II 1012-61.5 ex Vista

2) - Synperonic A3 ex ICI

3) - Hydrophobically modified silica

Conditions:

30 minutes wash; 18°FH water; non-fluorescent cotton; liquor:cloth ratio 40:1; NAL-base (4.5 g/1) ; TAED (5% on product); sodium perborate monohydrate (10.5% on product) .

4) • No fluorescer ® Tinopal DMS ex Ciba Geigy (see EP-A-0, 364, 027) D Tinopal CBS-X es Ciba Geigy(see EP-A-0,364,027) X Compound (2) of EP-A-0,364,027 1 Compound (2) of the invention

The diagram of Figure 1 illustrates the most favourable dependency of the whitening performance of the FWA compound (2) of the invention on temperature, as compared to other FWA compounds of the art. The sharp fall-off in performance at low temperatures is surprising and was much less with other benzofurans investigated.

Examples II and III

The following NAL-detergent composition was prepared wherein different types of fluorescent whitening agents were incorporated. The compositions were stored and % fluorescent whitening agent (FWA) remaining after 1 day, 2 weeks, 4 weeks and 12 weeks was determined.

NAL-Detergent composition parts by weight Nonionic¹* 23

Nonionic^2} 19

Dodecyl benzene sulphonic acid 6

Glyceroltriacetate 5

Sodium carbonate 18 Calcite 7

Na-carboxymethylcellulose 1.5

Sipernat D17 3

Silicone DB 100 1.2

Enzyme (Savinase/Lipolase) 0.8 Sodium perborate monohydrate 10

TAED 5

Fluorescent whitening agent 0.15

Perfume balance

The results are shown in the following tables.

Table 1

Table 2

* Blankophor BHC (= Blankophor CKS) ex Bayer, once known as super-brightener (for formula see EP-A-0, 364 , 027) .

Claims

1. A non-aqueous liquid detergent composition comprising a surfactant, a builder and a fluorescent whitening agent, characterized in that the fluorescent whitening agent (FWA) is a dibenzofuran-diphenyl compound of the formula (I) :

wherein R¹ is a C^C^ alkyl or a phenyl group; R is hydrogen, a C₁-C₄ alkyl or alkoxy group, or phenoxy group; and M is hydrogen and/or a non-chromophoric cation.

2. A composition according to claim 1, characterized in that said R¹ is a C₁-C₄ alkyl group, and R is hydrogen or a C_λ-C₄ alkyl group.

3. A composition according to claim 2, characterized in that the FWA is a compound of the formula (1)

4 . A composition according to claim 2 , characterized in that the FWA is a compound of the formula ( 2 )

A composition according to any of the preceding claims 1.

1-4, characterized in that it further comprises an oxygen bleach.

6. A composition according to claim 5, characterized in that said oxygen bleach comprises a persalt and a bleach precursor.

7. A composition according to claim 6, characterized in that said precursor is selected from TAED and the class of hydrophobic bleach precursors.

8. A composition according to claim 5, characterized in that said oxygen bleach comprises a peroxyacid compound.

9. A composition according to claim 8, characterized in that said peroxyacid compound is DPDA or PAP.

10. A liquid detergent composition comprising a surfactant, a builder and a dibenzofuran-diphenyl fluorescent whitening agent of formula (I) :

wherein R¹ is a C -C₄ alkyl or a phenyl group; R is hydrogen, a C -C^ alkyl or alkoxy group, or phenoxy group; and M is hydrogen and/or a non-chromophoric cation packed in a transparent or translucent container.