Field of the Invention

The present invention relates to a stain repellence composition for treating a substrate. More particularly the present invention relates to a composition for hydrophilic stain repellence and process for making a substrate repellent to hydrophilic stains.

Background and Prior Art

Present days consumers are not only looking for fabric washing composition to remove the dirt. But, they are also looking for fabric treatment composition before-wash or after-wash to keep the fabric better and long-lasting. Different types of fabric care/treatment compositions are known in the art. Fabric care compositions serve a variety of purposes. The use of a fabric care composition is one of the ways to deliver and deposit different types of benefit agents onto the fabrics.

Fabric cleaning or care compositions that provide a so called next time cleaning benefit, are highly appreciated by present day consumers. By next time cleaning benefit is meant any treatment of a substrate prior to the deposition of dirt that enables easier cleaning upon the subsequent cleaning.

Similarly there is a need for compositions for the treatment of hard and soft surfaces (e.g. kitchen tops, tiles, carpets, upholstery, windows, including car windscreens, etc) that render the surfaces hydrophobic and/or repellent to aqueous stains. Fabrics need to be cleaned from time to time depending on the perception of the cleanliness of the consumers. However, washing a fabric causes fabric damage. The more often a garment is washed, the more is the damage to the fabric. The damage of the fabric leads to the weariness and which subsequently leads to the older appearance of the fabric.

One of the ways of keeping fabrics clean is not to expose it to the environment which will eventually make the fabric dirty. Less dirty the fabric is the frequency of washing will also be less. Due to reduced frequency of fabric washing the weariness will also be less and the fabrics will become long lasting. Coating compositions using different fabric compatible polymers to reduce the dirt on the fabric have been disclosed in the art.

WO 91/04305 discloses an aqueous water repellent composition comprising the reaction product of one or more of a carboxylic acid or anhydride containing from 3 to 22 carbon atoms and a polyfunctional aromatic or aliphatic amine or substituted amine containing from 2 to 25 carbon atoms and a water soluble metal complex crosslinking agent containing one or more metals selected from Groups la, lla, Ilia, IVa and the first and second rows of transition metals from the Periodic Table of Elements. The composition may contain wax and is dispersed in water to form a water repellent system.

GB 849275 discloses an anti-fungal composition for treating fabrics comprises an aqueous solution containing a thermosetting aminoplastic resin and a water-soluble complex of 8-hydroxyquinoline with copper and chromium.

GB 1257107 discloses compositions for rendering a fabric water repellent by means of the application of metal soaps. WO 2008/148610 (co-pending) discloses a zinc complex for water repellence, however, the present inventors have found that this composition is difficult to formulate in the form of an easy to use direct application product.

WO 2010/057743 (co-pending) discloses compositions comprising Zinc, and amino compound and soap.

A composition which will make a substrate (e.g. fabrics and/or surfaces) hydrophobic and therefore repellent soils and stains, which are hydrophilic in nature, remains to be desired.

In view of the foregoing, it is an object of the present invention to provide a composition that renders a substrate hydrophobic; and thereby make a substrate repellent to hydrophilic stains. It is another object of the invention to provide substrates that are resistant to getting soiled or stained by hydrophilic stains.

It is yet another object of the invention to provide a direct application composition for treating substrates.

Surprisingly it has now been found that, a complex of zinc and triethanolamine in the presence of soap and a salt of a trivalent metal ion and/or tetravalent metal ion in an alcohol based medium is suitable for use as a direct application hydrophilic stain repellence composition on the substrate and can make the substrate hydrophobic.

Summary of the invention

Accordingly the invention provides a liquid direct application composition for treating a substrate comprising 0.25-5% by weight of a stain repellence composition comprising 25-50% by weight of the stain repellence composition of a soap; 10-30% by weight of the stain repellence composition of a complex of zinc and triethanolamine (TEA); 30- 65% by weight of the stain repellence composition of a salt of a trivalent metal ion and/or tetravalent metal ion a solvent comprising a lower alcohol and water in a ratio of between 99:1 and 85:15.

In another aspect the invention provides a process for making a substrate hydrophilic stain repellence comprising the steps of applying the composition according to any one of the preceding claims onto a substrate; and drying the substrate. In yet another aspect the invention provides the use of a composition according to any one of claims 1 to 4 to make a fabric hydrophobic.

In still another aspect the invention provides a trigger spray dispenser comprising the composition according to any one of claims 1 -4.

By the term hydrophilic stain repellence in the present invention is meant that, the composition according to the invention will make a substrate hydrophobic. Due to the enhanced hydrophobicity of the substrate, it will not attract any hydrophilic material therefore becomes repellent to hydrophilic stains. These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description. For the avoidance of doubt, any feature of one aspect of the present invention may be utilised in any other aspect of the invention. The word "comprising" is intended to mean "including" but not necessarily "consisting of" or "composed of." In other words, the listed steps or options need not be exhaustive. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se. Similarly, all percentages are weight/weight percentages unless otherwise indicated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word "about". Numerical ranges expressed in the format "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also contemplated.

Detailed description of the invention

According to the present invention a liquid direct application composition for treating a substrate is provided, which comprises a stain repellence composition and a solvent comprising a lower alcohol and water.

Stain repellence composition.

The stain repellence composition comprises a soap, a complex of zinc and triethanolamine (TEA) and a salt of a trivalent metal ion and/or tetravalent metal ion.

Soap

The soap according to the invention is present in a concentration of between 25 and 50% of the stain repellence composition, preferably at least 30%, more preferably at least 35%, but preferably less than 45% by weight of the stain repellence composition.

The soap is a preferably selected from C ₈ -C ₂ o soap, preferably Ci ₂ -Ci ₆ soap, more preferably C12-C14 soap. The cation is selected from alkali metals. Alkaline earth metals are generally not preferred. Non-limiting examples of water-soluble soaps that can be used according to the present invention include sodium or potassium laurate, sodium or potassium caprylate, and sodium/potassium myristate and mixtures thereof.

By saturated soap is meant in the context of the present invention that the iodine value of the soap, which is commonly known and used in the art to indicate the degree of unsaturation, is preferably less than 20, more preferably less than 10, and most preferably less than 5. Saturated soap having no carbon-carbon double bond or triple bond is particularly preferred.

Complex of zinc and triethanolamine

The complex of zinc and triethanolamine is present in a concentration of 10-30% by weight of the stain repellence composition. The complex is preferably present in a concentration of at least 15%, but preferably not more than 25% by weight of the stain repellence composition.

The present invention relates to a complex of Zinc having the empirical formula Zn _x (TEA) _y (BB) _z , where; "TEA" is triethanolamine, also known as TEAH ₃ , wherein the TEA may be present in the complex in a deprotonated state, such as TEAH; "BB" represents carboxylate groups of the formula H(CH ₂ ) _P C02 ^" , where p = 1 -5, which are bonded to Zinc either by terminal or bridged oxygen atoms; and, x, y and z are integers that satisfy the bivalency of zinc, wherein x is preferably at least 2. A formula of the structure is found below.

In a preferred form, the carboxylate groups are represented by the formula,

H(CH ₂ )pC0 ₂ ^" , where p = 1 -5. This includes Acetic acid, Propionic acid, Butyric acid, Valeric acid and Caproic acid. It is preferred that the acid is Acetic acid. Salt of a trivalent metal ion and/or tetravalent metal ion

The trivalent cation is preferably selected from cations of aluminium, titanium (III), chromium or iron (III) or mixtures thereof. These trivalent ions are preferably added to the composition in the form of their salts. If the trivalent metal ion is aluminium the counter ion is preferably selected from chloride, nitrate, sulphate, acetate or formate or mixtures thereof, more preferably chloride, nitrate, sulphate, and mixtures thereof. The most preferable trivalent salts are selected from aluminium chloride, titanium (III) chloride, ferric chloride, chromium chloride, aluminium nitrate, chromium nitrate, ferric nitrate. The tetravalent metal ion is preferably selected from titanium (IV). The preferred salt of the tetravalent metal ion is selected from titanium (IV) chloride.

The salt of a trivalent metal ion and/or tetravalent metal ion is present in a concentration of 30-65% by weight of the stain repellence composition. The stain repellence composition preferably comprises at least 35%, but preferably not more than 60%, more preferably not more than 55%, still more preferably not more than 50%, or even not more than 45% by weight of the stain repellence composition.

Solvent

The liquid direct application composition further comprises a solvent. The solvent comprises a lower alcohol and water.

The lower alcohol is an alcohol comprising from 1 to 4 carbon atoms, more preferably selected from methanol, ethanol, propanol, preferably 2-propanol.

These lower alcohols typically contain low amounts of water, typically 1 -5%. A low amount of additional water may optionally be added. The ratio between the lower alcohol and water is typically between 99:1 and 85:15, more preferably the ratio is between 98:2 and 90:10, or even between 97:3 and 95:5.

Liquid direct application composition

The liquid direct application composition preferably comprises between 1 and 5% of the stain repellence composition in the solvent, more preferably at least 2% by weight, but the composition more preferably comprises less than 4%by weight of the stain repellence composition in the solvent. The liquid direct application compositions may be packaged in a trigger spray dispense, a roll-on dispenser or any other kind of direct application dispenser. A trigger spray dispenser is the most preferred.

Treating a substrate

The substrate may be any substrate and includes hard and soft surfaces (e.g. fabrics, carpets, upholstery, metal surfaces, kitchen tops, tiles, windows, including car windscreens, etc).

In one embodiment the invention provides a process for making a substrate hydrophilic stain repellent comprising the steps of: (a) applying the direct application composition according to the invention onto a substrate, and (b) drying and optionally ironing the substrate. The direct application step is to ensure that the surface of the substrate is substantially coated by the composition of the invention. It will be appreciated that any other means apart from spraying, that give rise to the coating of a substrate.

According to one of the preferred aspect of the present invention the drying step is carried out at an ambient temperature, i.e. 20-25°C, but, it also can be carried out at an elevated temperature. Now the invention will be demonstrated by way of non-limiting examples. Examples

The examples are for illustration only and do not limit the scope of the invention in any manner. Example 1 : Making a Zn-triethanolamine complex

Zn acetate dihydrate (Merck) and TEA (Merck) were ground together at a molar ratio of 2:1 for 30 minutes using a mortar and pestle. The solid mass obtained after the mixing was washed with ethanol (99%) twice, purified and the residue was dried at 60 C for 4 hours. The material was characterized by FT-IR and Powder X-Ray diffraction. The complex as isolated has a molecular formula Zn ₄ (OAc-t) ₂ (OAc-b)2(TEAH)2 where t means terminal and b means bridging ligand respectively.

Example 2: Making a Zn-TEA complex

1 1 g (0.05M) Zinc acetate 2H ₂ 0 AR (Ex Merck) was taken in a round bottom flask and 500 ml Ethanol (HPLC grade absolute alcohol) was added to it. The alcohol was evaporated on rotary evaporator till about 250 ml alcohol was evaporated. The flask was then cooled in ice bath to 0°C.

In a 250ml beaker, 7.45g Triethanolmine AR (ex. SD Fine Chem) was dissolved in 100ml absolute alcohol. This solution was added dropwise to the round bottom flask containing alcoholic solution of Zinc acetate with constant stirring. A transparent sol was obtained. The alcohol was then evaporated to get the Compound-1 A in the form of a white powder. The material was characterized as having the molecular formula Zn ₄ (OAc-t) ₂ (OAc-b) ₂ (TEAH) ₂ .

Example 3: Water repellence tests

Twenty compositions (see table below) were prepared, with at least one of the ingredients for the stain repellence composition. Compositions 1 to 4, 22 and 23 contain all 3 required ingredients; in compositions 5 to 20 at least one of the required ingredients is not present and in composition 21 none are present. In compositions 1 -

21 , the treatment composition was dissolved in ethanol (99.9%) and in compositions 22 and 23, the composition was dissolved in water. The table shows the relative concentration of the 3 ingredients by weight of the total amount of ingredients of the stain repellence composition, and the concentration of the total stain repellence composition in the solvent.

Compositions 1 -21 are clear solutions, compositions 22 and 23 are turbid.

Desized cotton fabric swatches (of 100 cm ² ex, Bombay Dyeing) are treated by adding 3 mL of any of the above mentioned compositions by a pipette. The swatches were then dried in air. The fabric was ironed at a temperature of 105 °C. Water repellency was checked by the so called Drop test method.

Drop test method

This test determines a treated fabric's resistance to wetting by aqueous liquids. Drops of water-alcohol mixtures of varying surface tensions are placed on the fabric, and the extent of surface wetting is determined visually. This test provides a rough index of aqueous stain resistance; the higher the solution number up to which the fabric does not wick, the more water repellent the fabric is.. The test solutions used for the experiment are as follows:

The fabric swatches were treated as follows. The test fabric was placed face up on a glass microscopic slide. Beginning with Test Liquid No. 0, 10 μΙ_ droplet of the solution was placed on the test fabric. The drop was observed for 10 seconds from an approximate 45° angle. If the droplet did not wet the fabrics then the next mixture solution was added in the same manner. The fabric's water repellency rating was the highest numbered liquid for which at the droplet did not wet or wick into the fabric. The results are given in the table below Drop test result score

1 2

2 4

3 4

4 2

5 0

6 0

7 0

8 0

9 0

10 0

1 1 0

12 0

13 0

14 0

15 0

16 0

17 0

18 0

19 0

20 0

21 0

22 0

23 0

The above results show that only when all 3 ingredients (Zn-TEA, Soap and a tri- or tetra-valent metal) are present in the composition, the required effect is obtained. Example 4: treatment of a hard surface

0.5 mL of composition 2 (see above) was added to a glass slide and a stainless steel plate, left for drying and wiped off with a tissue paper till completely dry.

The contact angle (degree) was measured by putting a 10 microlitre of water droplet on the treated and the untreated surfaces. untreated Treated

Glass slide 16 80

Stainless steel 42 75

The higher the contact angle the higher the water repellence.