TRIPHENYL METHANE AND XANTHENE PIGMENTS

FIELD OF INVENTION

The present invention concerns the use of organic pigments in laundry compositions.

BACKGROUND OF INVENTION

Many garments yellow over multiple wash wear cycles, reducing the aesthetic value of the garment. In order to maintain the white appearance shading dyes may be used.

Colouring agents, when substantive to a fabric, are normally specific to a particular fibre type, for example cotton or polyester. WO 2006/032397 discloses the use of differing dye types in order to garments of differing fabrics and shade mixed garment fibres.

SUMMARY OF INVENTION

We have found that blue and violet pigments based on triphenyl methane and xanthene chromphores with inorganic heteropolyacids efficiently deposit onto cotton, polyester and nylon. A consequence is that the pigments of the present invention may be used as a chromophore alone, i.e. without other blue/violet shading agents.

In one aspect the present invention provides laundry composition comprising between 0.00001 to 0.01 wt% of an

organic pigment and 2 to 70 wt% of a surfactant, wherein the organic pigment is an inorganic heteropolyacid salt of a triphenyl methane or a xanthene moiety.

DETAILED DESCRIPTION OF INVENTION

Organic pigments are described in industrial Organic Pigments', Wiley VCH 2004 by W.Herbst and K. Hunger. Dyes are organic chemicals that are soluble in their application medium. Pigments are inorganic or organic particles that are insoluble in their application medium.

The present invention concerns pigments of the structure

Where the anion A is an inorganic heteropolyacid. The heteropolyacid is preferably selected from phosphomolybdic acid, phosphotungstic acid, phosphotungstomolybdic acid and silicomolybdic acid.

In the structures below the arrow indicates position of bonding to the pigment core structure.

Preferred pigments are triphenyl methane, when O is absent, or a xanthene moiety, when O is present and bonded at dashed lines, of the following form:

wherein A- is an inorganic heteropolyacid;

Rl and R2 are independently selected from: hydrogen, C1-C6- alkyl and phenyl;

X is independently selected from the group consisting of: hydrogen, Cl-C6-alkyl and benzyl;

Ar is selected is hydrogen,

Cl-C6-alkyl or wherein Rl and R2 are as defined above; R3 is hydrogen, Cl-C6-alkyl, or phenyl; R ₄ is hydrogen, Cl-C6-alkyl, or phenyl.

The Ri and R2 groups are independently selected from hydrogen, methyl and ethyl groups, preferably methyl and ethyl. Preferably the Rl groups are same. Preferably the Rl groups are the same and the R2 groups are the same.

X is selected from hydrogen and methyl, preferably hydrogen,

- A -

The central oxygen shown with dashed bonds is optional; the triphenyl methane pigments are most preferred.

When the central Oxygen atom is present, then the Ar group is preferably

, in which Y is selected from hydrogen, methyl and ethyl groups .

In the absence of the central oxygen the Ar group is preferably selected from:

where the R ₃ is selected from hydrogen, methyl or ethyl, preferably hydrogen and R ₄ is selected from methyl, ethyl or phenyl. The amine substituted phenyl group is preferred rather than the naphthyl .

Preferred pigments are pigment violet 3, pigment violet 27, pigment violet 39, pigment violet 1, pigment violet 1:1, pigment violet 1:2, pigment blue 1, pigment blue 1:2,

pigment blue 1:3 pigment blue 2, pigment blue 10, pigment blue 10:1, pigment blue 11, pigment blue 14 and pigment blue 62.

Most preferably pigment violet 3, pigment violet 27, pigment violet 39 and pigment blue 14.

It is most preferred that pigments are used alone and not in combination with other blue or violet shading dyes. In this regard the laundry composition contains less than 0.00004 wt% of a blue or violet shading dye and is preferably devoid of such.

SURFACTANT

The composition comprises between 2 to 70 wt% of a surfactant, most preferably 10 to 30 wt %. In general, the nonionic and anionic surfactants of the surfactant system may be chosen from the surfactants described "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 Ce 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 Cs to Cis primary or secondary linear or branched alcohols with ethylene oxide, generally 5 to 40 EO.

Suitable anionic detergent compounds which may be used are usually 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 Cis alcohols, produced for example from tallow or coconut oil, sodium and potassium alkyl Cg to C20 benzene sulphonates, particularly sodium linear secondary alkyl Cio to Ci ₅ 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 preferred anionic detergent compounds are sodium Cu to Ci ₅ alkyl benzene sulphonates and sodium C ₁₂ to Cis alkyl sulphates. 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 .

Preferred surfactant systems are mixtures of anionic with nonionic detergent active materials, in particular the groups and examples of anionic and nonionic surfactants pointed out in EP-A-346 995 (Unilever) . Especially preferred is surfactant system that is a mixture of an alkali metal

salt of a Ci6 to Cis primary alcohol sulphate together with a Ci2 to Ci5 primary alcohol 3 to 7 EO ethoxylate.

The nonionic detergent is preferably present in amounts greater than 10%, e.g. 25 to 90 wt % of the surfactant system. Anionic surfactants can be present for example in amounts in the range from about 5% to about 40 wt % of the surfactant system.

In another aspect which is also preferred the surfactant may be a cationic such that the formulation is a fabric conditioner .

CATIONIC COMPOUND

When the present invention is used as a fabric conditioner it needs to contain a cationic compound.

Most preferred are quaternary ammonium compounds.

It is advantageous if the quaternary ammonium compound is a quaternary ammonium compound having at least one C12 to C22 alkyl chain.

It is preferred if the quaternary ammonium compound has the following formula:

R2

I ₊

R1—N-R3 X I R4 in which R ¹ is a C12 to C22 alkyl or alkenyl chain; R ² , R ³ and R ⁴ are independently selected from Ci to C ₄ alkyl chains and X ^~ is a compatible anion. A preferred compound of this type

is the quaternary ammonium compound cetyl trimethyl quaternary ammonium bromide.

A second class of materials for use with the present invention are the quaternary ammonium of the above structure in which R ¹ and R ² are independently selected from C12 to C22 alkyl or alkenyl chain; R ³ and R ⁴ are independently selected from Ci to C ₄ alkyl chains and X ^~ is a compatible anion.

A detergent composition according to claim 1 in which the ratio of (ii) cationic material to (iv) anionic surfactant is at least 2:1.

Other suitable quaternary ammonium compounds are disclosed in EP 0 239 910 (Proctor 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 1.5 wt % to 50 wt % of the total weight of the composition. Preferably the cationic compound may be present from 2 wt % to 25 wt %, a more preferred composition range is from 5 wt % to 20 wt %. The softening material is preferably present in an amount of from 2 to 60% by weight of the total composition, more preferably from 2 to 40%, most preferably from 3 to 30% by weight .

The composition optionally comprises a silicone.

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-l , 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.

Examples

Pigment Violet 1:2 Phosphotungstomolybdic acid salt of

Pigment violet 3 Phosphotungstomolybdic acid salt of

Pigment Violet 39 Phosphomolybdic salt of

Pigment Blue 1 Phosphotungstomolybdic acid salt of

Pigment violet 14 is an inorganic pigment based on (Co) ₃ (P0 ₄ ) ₂

Example 1 Pigments were tested for shading benefit by washing cotton, polyester-cotton, polyester, nylon-elastane fabric together at room temperature, in 2. Og/L of a base washing powder which contained: 18% NaLAS, 73% salts (silicate, sodium tri- poly-phosphate, sulphate, carbonate) , 3% minors including fluorescer and enzymes, remainder impurities and water. A liquor to cloth of with a 30:1 was used, the wash lasted for 30 mins, and were conducted with and without the addition of 500 part per billion of the pigment. Pigments were added from a 0.005 wt% solution in ethanol. All pigments were used as received. Following the wash, the cloths were rinses then drying. The colour of the cloth was then assessed using a reflectometer (UV excluded for all measurements) and expressed as the δE value relative to cloth washed without pigment. The pigments tested and δE values are given in the table below.

AIl the triphenyl methane and xanthene based pigments showed good deposition over the range of the fabrics. In contrast, the inorganic pigment violet 14 shows very low deposition on these fabrics.

Fabric codes:

WC = woven cotton

KC = knitted cotton

WP = woven polyester

WPC = 65/35 woven polyester cotton

NE = 90/10 nylon elastane