WO1996023051A1

WO1996023051A1 - Detergent composition containing bactericidally and photooxidatively active titanium dioxide

Info

Publication number: WO1996023051A1
Application number: PCT/FR1996/000073
Authority: WO
Inventors: Thierry Chopin; Jean-Pierre Cuif
Original assignee: Rhone-Poulenc Chimie
Priority date: 1995-01-25
Filing date: 1996-01-17
Publication date: 1996-08-01
Also published as: AU4543796A; FR2729673A1; FR2729673B1

Abstract

A detergent composition containing titanium dioxide in the form of elementary particles having a size of less than 100 nm and a specific surface area greater than 150 m2/g, and the use of said titanium dioxide as a bactericidal and photooxidative agent in a detergent composition.

Description

DETERGENT COMPOSITION CONTAINING TITANIUM DIOXIDE WITH BACTERICIDAL AND PHOTO-OXIDIZING FUNCTION

The invention relates to a detergent composition containing titanium dioxide in the form of elementary particles of size less than 100 nm and of specific surface greater than 150 m ² / g.

It also relates to the use of said titanium dioxide as a bactericidal and photo-oxidizing agent in a detergent composition. In any type of detergency, whether for washing clothes or for industrial surfaces such as tiles, windows, etc., it is essential to be able to destroy microorganisms such as bacteria, algae, microscopic fungi, animal cell residues or plants .... which may cause risks to human health. In fields of application other than detergency, a certain number of techniques are known for eliminating these microorganisms, such as irradiation under gamma or UV radiation, freezing, sterilization by heating, etc. However, these techniques are difficult to apply in detergency and we generally favor bactericidal chemical agents and in particular oxidizing agents such as hydrogen peroxide or bleach. These chemicals can however have drawbacks such as, for example, those of damaging the linen or difficult to remove from waste water (chlorine).

The object of the present invention is to provide a means other than chemical agents for eliminating microorganisms in detergency.

For this purpose, the invention relates to a detergent composition comprising titanium dioxide, as well as the use of titanium dioxide as a bactericidal and photo-oxidizing agent in a detergent composition.

The invention relates first of all to a detergent composition characterized in that it contains titanium dioxide in the form of elementary particles of size less than 100 nm, preferably less than 70 nm, very particularly of the order of 20 to 60 nm and with a specific surface greater than 150 rrvVg, preferably greater than 200 m / g, very particularly of the order of 200 to 300 m ² / g.

Titanium dioxide has a photocatalytic action in an aqueous medium and in the presence of UV rays, with the release of oxidizing species, which can have a bactericidal or soil degradation effect. Titanium dioxide is also a bleaching activator, in particular an activator of the decomposition of hydrogen peroxide with release of more oxidizing species.

The specific surface described above is a BET surface. O means BET surface, the specific surface determined by nitrogen adsorption in accordance with standard ASTM D 3663-78 established from the method

BRUNAUER - EMMETT - TELLER described in the periodical "The Journal of the American Society", fiQ, 309 (1938).

The failure of elementary titanium dioxide particles according to the invention is measured by transmission electron microscopy (TEM).

The nature of the elementary particles of titanium dioxide is preferably the anatase.

Said elementary titanium dioxide particles can be present, within the detergent composition, both in the form of aggregates and of individualized particles, as in colloidal dispersion depending on the physical nature of the detergent composition.

Thus, for example, if the detergent composition is a powder, the elementary particles of titanium dioxide will generally be present in the form of aggregates. They can also be deposited on the surface of an inorganic substance inert with respect to titanium dioxide such as alkali metal carbonate.

If the detergent composition is liquid, the elementary particles of titanium dioxide can be perfectly individualized and well separated from each other. Thus, said elementary particles of titanium dioxide can be in the form of a colloidal dispersion.

By colloidal dispersion is meant here and for the entire description any system consisting of fine particles of colloidal size based on titanium oxide and / or hydrated oxide (hydroxide), suspended in a liquid phase, in particular an aqueous phase. Titanium can be found either completely in the form of colloids, or simultaneously in the form of ions and colloids, without however the proportion represented by the ionic form not exceeding approximately 10% of the total of titanium in the colloidal dispersion. According to the invention, colloidal dispersions are preferably used in which the titanium is completely in colloidal form. This colloidal dispersion generally has a solids content of between 5 and 30%, preferably between 10 and 20% by weight. The elementary particles of titanium dioxide according to the invention, either in the form of aggregates, or in the form of individualized particles, can be obtained by any means known to those skilled in the art.

Thus, they can be obtained by hydrolysis of a titanium compound, then recovery of the solid formed during this hydrolysis.

The hydrolyzed titanium compound can be chosen from halides, oxyhalides, nitrates, alkoxides or titanium sulfates.

The hydrolysis operation can be carried out by heating the solution of titanium compound. It can, in certain cases, be carried out in the presence of titanium dioxide seeds or in the presence of specific compounds making it possible to obtain titanium dioxide of higher purity, such as those described in

EP-A-0351 270.

Once the hydrolysis has been carried out, the precipitated titanium dioxide is separated from the mother liquors, then dried, the titanium dioxide powder obtained can be used directly or be redispersed in a liquid medium so as to obtain a colloidal dispersion of titanium dioxide .

It is also possible, after recovery of the solid obtained following the hydrolysis operation, to neutralize it and to subject it to at least one washing before it is re-dispersed. The solid can be recovered, for example by centrifugation of the solution obtained after hydrolysis. It is then neutralized with a base, for example an ammonia solution, then washed by redispersion in a basified aqueous solution. After separation of the solid from the aqueous washing phase and optionally one or more washes of the same type, the product is redispersed. In the detergent composition, the level of titanium dioxide, expressed in dry terms, may be at least about 0.1%, preferably of the order of 0.1 to 5%, very particularly of the order of 0.4 to 3% by weight of said composition.

The invention also relates to the use of titanium dioxide in the form of elementary particles having a size less than 100 nm, preferably less than 70 nm, very particularly of the order of 20 to 60 nm and a specific surface greater than 150 m ² / g, preferably greater than 200 m ² / g, very particularly of the order of 200 to 300 m ² / g, as a bactericidal and photo-oxidizing agent in a detergent composition. Titanium dioxide is capable of destroying living organic matter, so it acts as a bactericidal agent. It also destroys dead organic matter, it is a photo-oxidizing agent. These two functions of titanium oxide may be due to the photocatalytic process and or the bleach activating process described above.

According to the invention, the term “detergent composition” is understood to mean both detergent formulations, in particular for household or industrial washing of linen, as well as compositions for cleaning or maintaining hard surfaces exposed to light.

In the case of detergent compositions for washing clothes, titanium dioxide is deposited on the clothes at the time of washing, in the washing machine for example. The bactericidal and / or photo-oxidant effect then occurs when the linen which is still wet is removed from the machine and exposed to sunlight or electric lighting.

Besides the elementary particles of titanium dioxide, there can be found in the detergent composition for the laundry various additives such as:

- SURFACTANTS, in amounts corresponding to approximately 3 40% by weight relative to the detergent composition, surfactants such as anionic surfactants

. alkyl ester sulphonates of formula R-CH (Sθ3M) -COOR ', where is an alkyl radical containing 8 "20> ^preferably C- | o-Cl6>^R' ^an alkyl radica Ci-Cβ, preferably C1 C3 and M an alkali cation (sodium potassium, lithium), substituted or unsubstituted ammonium (methyl-, dimethyl- trimethyl-, tetramethylammonium, dimethylpiperidinium ...) or derived from an alkanolamine (monoethanolamine, diethanolamine, triethanolamine ...) Mention may very particularly be made of methyl ester sulfonates whose radicals R is C ₁ -C ₁₆ ;

. alkyl sulfates of formula ROSO3M, where R represents a C10-C24 alkyl or hydroxyalkyl radical. ^preferably C12-C20 and most preferably C12-C18 'M representing a hydrogen atom or a cation with the same definition as above, and their ethoxylenated (EO) and / or propoxylenated (PO) derivatives, having on average of 0.5 to 6 units, preferably 0.5 to 3 OE and / or OP units;

. the alkylamide sulfates of formula RCONHROSO3M where R represents a C2-C22 alkyl radical. preferably Cβ-C20. ^R ' ^a C2- alkyl radical

C3, M representing a hydrogen atom or a cation of the same definition as above, as well as their ethoxylenated (OE) and / or propoxylenated (OP) derivatives, having on average from 0.5 to 60 OE units and / or OP;

. the salts of C8-C24, preferably C14-C20 saturated or unsaturated fatty acids. 'C9-C20 alkylbenzenesulfonates. primary alkyl sulfonates or secondary in C8-C22. alkyl glycerol sulfonates, sulfonated polycarboxylic acids such as those described in GB-A-1 082 179, paraffin sulfonates, N-acyl N-alkyltaurates, alkylphosphates, isethionates, alkylsuccinamates, alkylsulfosuccinates, monoesters or diesters of sulfosuccinates, N-acyl sarcosinates, alkyl glycoside sulfates, polyethoxycarboxylates, the cation being an alkali metal (sodium, potassium, lithium), a substituted or unsubstituted ammonium residue (methyl-, dimethyl-, trimethyl-, tetramethylammonium, dimethylpiperidinium ...) or derived from an alkanolamine (monoethanolamine, diethanolamine, triethanolamine ...); non-ionic surfactants polyoxyalkylenated (polyethoxyethylenated, polyoxypropylenated, polyoxybutylenated) alkylphenols in which the alkyl substituent is C6-C12 and containing from 5 to 25 oxyalkylene units; by way of example, mention may be made of the Triton X-45, X-114, X-100 or X-102 sold by Rohm & Haas Cy. ; . glucosamide, glucamide, glycerolamide;

. polyoxyalkylenated C8-C22 aliphatic alcohols containing from 1 to 25 oxyalkylene units (oxyethylene, oxypropylene); by way of example, mention may be made of TERGITOL 15-S-9, TERGITOL 24-L-6 NMW sold by Union Carbide Corp., NEODOL 45-9, NEODOL 23-65, NEODOL 45-7, NEODOL 45-4 marketed by Shell Chemical Cy., KYRO EOB marketed by The Procter & Gamble Cy.

. the products resulting from the condensation of ethylene oxide the compound resulting from the condensation of propylene oxide with propylene glycol, such as the Pluronic sold by BASF;

. the products resulting from the condensation of ethylene oxide the compound resulting from the condensation of propylene oxide with ethylenediamine, such as TETRONIC sold by BASF;

. amine oxides such as alkyl oxides C10-C18 dimethylamines, alkoxy oxides C8-C22 ethyl dihydroxy ethylamines;

. the alkylpolyglycosides described in US-A-4,565,647; . amides of C8-C20 fatty acids. ethoxylated fatty acids. ethoxylated fatty amides. ethoxylated amines cationic surfactants. alkyldimethylammonium halides' amphoteric and zwitterionic surfactants . alkyldimethylbetaines, alkylamidopropyldimethylbetaines, alkyltrimethylsulfobetaines, Iles of condensation of fatty acids and protein hydrolysates.

- AGENTS IMPROVING THE PROPERTIES OF SURFACTANTS ("builders") in amounts corresponding to about 5-50%, preferably about 5-30% by weight for liquid detergent formulas, or about 10-80%, d preferably 15-50% by weight for detergent formulas in powders, such as inorganic Cbuilders ")

. polyphosphates (tripolyphosphates, pyrophosphates, orthophosphates hexametaphosphates) of alkali metals, ammonium or alkanolamines. tetraborates or borate precursors

. silicates, in particular those having a Siθ2 / Na2θ ratio of the order of 1.6 / 1 to 3.2 / 1 and the lamellar silicates described in US-A-4,664,839. alkali or alkaline earth carbonates (bicarbonates, sesquicarbonates)

. crystalline or amorphous aminosilicates of alkali metals (sodium, potassium) or ammonium, such as zeolites A, P, X ...; zeolite A with a particle size of the order of 0.1-10 micrometers is preferred organic agents ("builders") water-soluble polyphosphonates (1-hydroxy-1 ethane, 1-diphosphonates, methylene salts diphosphonates ...)

. water-soluble salts of carboxylic polymers or copolymers or their water-soluble salts such as

. polycarboxylate ethers (oxidisuccinic acid and its salts, monosuccinic acid tartrate and its salts, disuccinic acid tartrate and its salts. hydroxypolycarboxylate ethers

. citric acid and its salts, mellitic acid, succinic acid and their salts

. the salts of polyacetic acids (ethylenediaminetetraacetates, nitrilotriacetates, N- (2 hydroxyethyD-nitrilodiacetates), C5-C20 alkyl succinic acids and their salts (2-dodecenylsuccinates, lauryl succinates,)

. polyacetal carboxylic esters. polyaspartic acid, polyglutamic acid and their salts. polyimides derived from the polycondensation of aspartic acid and / or glutamic acid

. polycarboxymethylated derivatives of glutamic acid or other amino acids - WHITENING AGENTS, in amounts of about 0.1-20%, preferably about 1-10% by weight, optionally combined with WHITENING ACTIVATORS, in amounts of about 0.1-60%, preferably about 0.5-40% by weight, agents and activators such as bleaches

. perborates such as sodium perborate monohydrate or tetrahydrate

. peroxygenated compounds such as sodium carbonate peroxyhydrate, pyrophosphate peroxyhydrate, urea peroxyhydrate, sodium peroxide, sodium persulfate preferably combined with a bleach activator generating in situ in the washing medium, a peroxyacid carboxylic acid; among these activators, there may be mentioned, tetraacetylethylene diamine, tetraacetyl methylene diamine, tetraacetyl glycoluryl, p-acetoxybenzene sodium sulfonate, pentaacetyl glucose, octaacetyl lactose ...

. percarboxylic acids and their salts (called "percarbonates") such as magnesium monoperoxyphthalate hexahydrate, magnesium metachloroperbenzoate, 4-nonylamino-4-oxoperoxybutyric acid, 6-nonylamino-6-oxoperoxycaproic acid, diperoxydodecanedioic acid, nonylamide peroxysuccinic acid, decyldiperoxysuccinic acid.

These agents can be combined with at least one of the anti-fouling or anti-redeposition agents mentioned below.

Mention may also be made of non-oxygenated bleaching agents, acting by photoactivation in the presence of oxygen, agents such as sulfonated aluminum and / or zinc phthalocyanines

- ANTI-FOULING AGENTS, in amounts of the order of 0.01-10%, preferably about 0.1-5%, and very particularly of the order of 0.2-3% by weight, agents such than . cellulose derivatives such as cellulose hydroxyethers, methylcellulose, ethylcellulose, hydroxypropyl methylcellulose, hydroxybutyl methylcellulose

. polyvinyl esters grafted on polyalkylene trunks such as polyvinylacetates grafted on polyoxyethylene trunks (EP-A-219 048). polyvinyl alcohols

. polyester copolymers based on ethylene terephthalate and / or propylene terephthalate and polyoxyethylene terephthalate units, with a molar ratio (number of units) ethylene terephthalate and / or propylene terephthalate / (number polyoxyethylene terephthalate of the order of 1/10 to 10/1, preferably of the order of 1/1 to 9/1, the polyoxyethylene terephthalates having polyoxyethylene units having a molecular weight of the order of 300 at 5,000, preferably in the range of 600 to 5,000 (US-A-3,959,230, US-A-3,893,929, US-A-116,896, US-A-4,728,857, US-A-4,770,666);

. sulfonated polyester oligomers obtained by sulfonation of an oligomer derived from ethoxylated allyl alcohol, dimethyl terephthalate and 1, propylene diol, having from 1 to 4 sulfonated groups (US-A-4968451)

. polyester copolymers based on propylene terephthalate and polyoxyethylene terephthalate units and terminated with ethyl or methyl units (US-A

4,711,730) or polyester oligomers terminated by alkylpolyethoxy groups (US-A-4,702,857) or anionic sulfopolyethox groups

(US-A-4721 580), sulfoaroyles (US-A-4877 896)

. the polyesters-polyurethanes obtained by reaction of a polyester of molecular mass in number of 300-4000 obtained from adipiquic acid and / or tereptalic acid and / or sulfoisophthalic acid and a diol of mass less than 300, on a prepolymer with terminal isocyanate groups obtained from a polyoxyethylene glycol with a molecular mass of 600-400 and a diisocyanate ((FR-A-2334698) - ANTI-REDEPOSITION AGENTS, in amounts of approximately 0 , 01-10% by weight for a powder detergent composition, of about 0.01 -5% by weight for a liquid detergent composition, agents such as

. ethoxylated monoamines or polyamines, ethoxylated amine polymers (US-A-4,597,898, EP-A-11,984). carboxymethylcellulose

. the sulfonated polyester oligomers obtained by condensation of isophthalic acid, of dimethyl sulfosuccinate and of diethylene glycol (FR-A-2 23 926)

. polyvinylpyrollidones - CHELATING AGENTS of iron and magnesium, in amounts of the order of 0.1-10%, preferably of the order of 0.1-3% by weight, agents such as

. aminocarboxylates such as ethylenediaminetetraacetates, hydroxyethyl ethylenediaminetriacetates, nitrilotriacetates

. aminophosphonates such as nitrilotris (methylene phosphonates) polyfunctional aromatic compounds such as dihydroxydisulfobenzenes - POLYMERIC DISPERSING AGENTS, in an amount of the order of 0.1-7% by weight. to control the hardness of calcium and magnesium, agents such as

. the water-soluble salts of polycarboxylic acids of molecular mass of the order of 2000 to 100,000, obtained by polymerization or copolymerization of ethylenically unsaturated carboxylic acids such as acrylic acid, maleic acid or anhydride, fumaric acid, itaconic acid, aconitic acid, mesaconic acid, citraconic acid, methylenemalonic acid, and in particular polyacrylates of molecular mass of the order of 2,000 to 10,000 (US-A-3,308,067), copolymers of arylic acid and maleic anhydride of mass molecular of the order of 5,000 to 75,000 (EP-A-66,915)

. polyethylene glycols of molecular mass of the order of 1000 to 50,000

- FLUORESCENCE AGENTS (BRIGHTENERS), in an amount of about 0.05-1.2% by weight, agents such as stilbene derivatives, pyrazoline, coumarin, fumaric acid, cinnamic acid,, azoles, methinecyanines, thiophenes. .. ("The production and application of fluorescent brightening agents" - M. Zahradnik, published by John Wiley & Sons, New York-1982-)

- FOAM SUPPRESSING AGENTS, in amounts up to 5% by weight, agents such as

. C- | 0'C24 monocarboxylic fatty acids or their alkali, ammonium or alkanolamine salts, fatty acid triglycerides

. aliphatic, alicyclic, aromatic or heterocyclic saturated or unsaturated hydrocarbons, such as paraffins, waxes. N-alkylaminotriazines

. monostearylphosphates, monostearyl alcohol phosphates

. polyorganosiloxane oils or resins optionally combined with silica particles

- SOFTENING AGENTS, in amounts of about 0.5-10% by weight, agents such as clays

- ENZYMES in quantities of up to 5 mg by weight, preferably of the order of 0.05-3 mg of active enzyme / g of detergent composition, enzymes such as

. proteases, amylases, lipases, cellulases, peroxidases (US-A-3 553 139, US-A-4 101 457, US-A-4 507 219, US-A-4261 868)

- OTHER ADDITIVES such as

. alcohols (methanol, ethanol, propanol, isopropanol, propanediol, ethylene glycol, glycerin) . buffering agents

. perfumes

. pigments.

The use of titanium dioxide according to the invention can also be done in detergent compositions for the maintenance of hard surfaces exposed to light. The level of titanium dioxide, expressed on a dry basis, may be at least about 0.1, preferably of the order of 0.1 to 5%, very particularly of the order of

0.4 to 3% by weight of said composition.

The specific surfaces exposed to light can be tiles, windows, car bodies, industrial surfaces, etc.

In this case, the bactericidal and / or photo-oxidant effect occurs as soon as the surface exposed to light is in contact with the detergent composition.

In the case of window washing, the detergent compositions can be made up of (percentages by weight):

- titanium dioxide particles according to the rates mentioned above,

non-ionic, zwitterionic or ampholytic organic surfactant, preferably a low-foaming surfactant, at a rate of 0.5 to 3%,

- inert organic solvent such as isopropanol, methanol, ethanol, acetone, 10 to 30%.

The balance consists of deionized water or a water / solvent mixture.

In the case of cleaning car bodies, the detergent compositions may consist of (percentages by weight):

- titanium dioxide according to the rates mentioned above

- 0-10% silicone oils - 0-10% wax - 10-30% solvent

- amorphous silica 0-5%

- non-ionic, zwitterionic or ampholytic organic surfactant 1-10%

- thickening agent (xanthan gum for example) 0-1% The balance of the composition consists of demineralized water.

The following examples illustrate the invention without, however, limiting it. EXAMPLES

EXAMPLE 1 Synthesis of a Colloidal Dispersion of Titanium Dioxide

Obtaining a titanium dioxide gel

A solution of titanyl sulfate resulting from the attack with illmenite sulfuric acid is hydrolyzed by raising the temperature. The solution obtained is centrifuged after hydrolysis so as to separate the acidic mother liquors from the solid which is in the form of a gel.

Gel wash and dispersion

This gel is neutralized with stirring with aqueous NH3 of 1 M concentration until pH = 8 and at a Tiθ2 concentration of 10% by weight. Washing is then carried out by a series of centrifugation-repulping operations (resuspension). The first four repulpages are carried out with a dilute NH4NO3 solution of concentration 7.10 ^-2 M, always at a Tiθ2 concentration of 10% by weight.

The fifth and last repulping is carried out at pH = 5 with NH4NO3 of 1 M concentration in order to desorb NH4 +.

Finally, the peptization is carried out by adding HNO3 with a concentration of 1 M up to pH = 1.6, and so as to have a Tiθ2 concentration of 15% by weight.

A colloidal dispersion of titanium dioxide is obtained in the anatase form, the colloids of which are 40 nm in size and have a specific surface of 250 m ² / g after drying at 200 ° C.

Example 2: comparison of the photocatalytic activity of a titanium dioxide according to the invention and another titanium dioxide.

An aqueous solution of K ₂ Cr ₂ θ7 is produced containing 0.05 g / l of Cr at degree of oxidation VI. The pH of the solution is 5.3.

20 ml of this solution are introduced into 3 transparent beakers of 50 ml volume.

The first is irradiated by a 200 W mercury lamp for 1 h.

In the second, a titanium dioxide powder having a specific surface after heating at 200 ° C. of 9 m ² / g and a particle size is added. of 200 nm, then irradiate the beaker in the same conditions as the first.

In the third, titanium dioxide having a specific surface area after heating at 200 ° C. of 187 m ² / g and an elementary particle size of 35 nm is added, then the beaker is irradiated under the same conditions as the other two .

After irradiation, the titanium dioxide is separated by centrifugation from solutions of the second and third beakers, then the total Cr is measured in each solution obtained by atomic adsorption, as well as the Cr (VI) pa visible UV spectrometry at 346 nm. The percentage of Cr (VI reduced to Cr (III) during the irradiation is thus measured.

The results are as follows:

Beaker 1 Beaker 2 Beaker 3 specific surface 9 m ² / g 187 m ² / g

% Cr (VI) reduced 0% 29.5% 100%

It is found that the titanium dioxide does indeed have a photocatalytic actio: the Cr (VI) of yellow color is reduced to Cr (III) of green color and on the other hand, it is observed that the titanium dioxide having the most specific surface area high has a photocatalytic activity significantly higher than that of titanium dioxide of low specific surface.

Example 3: comparison of the bactericidal effect of a colloidal dispersion of titanium dioxide according to the invention and of another titanium dioxide.

An S. Cerevisiae mold strain is grown for 12 hrs under aerobic conditions. The cells obtained are recovered and suspended in a phosphate buffer solution of 0.1 M concentration and pH = 7. The concentration of the cells is measured by a hemacytometer. We divide this suspension into two suspensions. In one, there is introduced a titanium dioxide powder having a specific surface of 35 m ² / g after drying at 200 ° C, an elementary particle size of 40 nm and marketed as a dispersion by Nippon Aerosil Ltd under the name P-25 In the other, the titanium dioxide powder obtained in Example 1 (after drying) is introduced and having a specific surface of 250 m ² / g and an elementary particle size of 45 nm

The titanium dioxide powders are introduced in such a way that the concentration is 10 ⁴ cells per mg of titanium dioxide. Then the mixtures are irradiated for 90 min by a 300 W Xenon lamp.

The percentage of cells killed is measured after 60, then 90 min. The cells are counted by the colony counting method on a petri dish.

The results are collated in the following table:

Tiθ2 surface Tiθ2 specific surface 35 m ² / g specific 250 m ² / g

Percentage of cells killed at 60 min 50% 80% at 90 min 70% 90%

It is observed that the titanium dioxide according to the invention is much more effective than a titanium dioxide with a smaller specific surface.

Example 4: Formulation for washing windows.

A formulation for washing windows is prepared by mixing the following constituents:

Isopropanol 20% deionized water 75%

PLURONIC F 48® (oxyethylene polyethylene glycol) 2% colloidal dispersion of titanium oxide from Example 1 3%

Example 5: Formula for cleaning car bodies A formulation for cleaning car bodies is prepared by mixing the following constituents:

polydimethylsiloxane oil (viscosity 1000 mPas. at 25 ° C) 5% polydimethylsiloxane oil (viscosity 3000 mPas at 25 ° C) 1% camauba wax 5% white spirit essence 15% . amorphous silica TIXOSIL 38® 3%

. lauryl ether sulfate (3 oxyethylene units) 2%

. ethoxylated C12 aliphatic alcohol (6 oxyethylene units) 3%

. xanthan gum RHODOPOL 23® 0.5%

>. titanium oxide of example 1 3%

. demineralized water 62.5%

Claims

1. Detergent composition characterized in that it comprises titanium dioxide in the form of elementary particles of size less than 100 nm, preferably less than 70 nm, very particularly of the order of 20 to 60 nm and of greater specific surface at 150 m ² / g, preferably greater than 200 m ² / g, very particularly of the order of 200 to 300 m ² / g.

2. A detergent composition according to claim 1 characterized in that the elementary particles of titanium dioxide are present in the form of a colloidal dispersion.

3. Detergent composition according to claim 2 characterized in that the colloidal aqueous dispersion of titanium dioxide has a solids content of between 5 and 30%, preferably between 10 and 20%.

4. Detergent composition according to one of claims 1 to 3 characterized in that the level of titanium dioxide expressed as dry is at least about 0.1%, preferably of the order of 0.1 to 5% , especially of the order of 0.4 to 3%.

5. Use of titanium dioxide in the form of elementary particles having a size less than 100 nm, preferably less than 70 nm, very particularly of the order of 20 to 60 nm and a specific surface greater than 150 m ² / g, preferably greater than 200 m ² / g, very particularly of the order of 200 to 300 m ² / g, as a bactericidal and photo-oxidizing agent in a detergent composition.

6. Use according to claim 5 in laundry compositions for washing clothes.

7. Use according to claim 5 in detergent compositions for the maintenance of hard surfaces exposed to light

8. Use according to any one of claims 5 to 7, characterized in that the level of titanium dioxide, expressed as dry, used is at least Approximately 0.1%, preferably of the order of 0.1 to 5%, very particularly of the order of 0.4 to 3% by weight of said composition.