EP4392522A1

EP4392522A1 - A concentrated cleaning composition

Info

Publication number: EP4392522A1
Application number: EP22769213.4A
Authority: EP
Inventors: Ramitha Kalathil; Robert John Carswell
Original assignee: Unilever Global IP Ltd; Unilever IP Holdings BV
Current assignee: Unilever Global IP Ltd; Unilever IP Holdings BV
Priority date: 2021-08-26
Filing date: 2022-08-25
Publication date: 2024-07-03
Anticipated expiration: 2042-08-25
Also published as: AR126878A1; CL2024000528A1; WO2023025884A1; CN117858937A; EP4392522B1; ZA202401507B

Abstract

The present invention is in the field of cleaning compositions. It relates to a concentrated liquid cleaning composition for forming a liquid detergent on dilution in water comprising: 10 to 50 wt% of an anionic surfactant selected from alkyl sulphate, alkyl ether sulphate, alkyl benzene sulphonate and combinations thereof; 1 to 10 wt% of an amphoteric surfactant; 1 to 20 wt% of a rhamnolipid; 1 to 10 wt% of a hydrotrope; and 0.1 to 15 wt% of a water-soluble inorganic salt, wherein the composition has a viscosity in the range 300 to 800 mPa.s and when diluted in water in 1:4 ratio by weight has a viscosity at least 1000 at 20 S^-1 shear rate, 25ºC, and wherein the pH of the composition is in the range from 4 to 7, wherein the ratio of rhamnolipid to hydrotrope is in the range from 1:1 to 6:1 by weight.

Description

A CONCENTRATED CLEANING COMPOSITION

Field of the invention

The present invention is in the field of cleaning compositions. In particular, it relates to a concentrated liquid cleaning composition for providing a liquid detergent on dilution in water.

Background of the invention

Consumers are involved in various cleaning activities as part of their household chores. Some of them may prefer to use cleaning compositions or products for better performance. Often products are available in various formats such as, bar, powder, liquid, tablet, or unit dose pod etc., and liquid is one of the preferred formats by consumers.

A cleaning composition in liquid format may contain detersive actives, sequestrants, bleaching agent, anti-foaming agent, enzyme, preservatives etc. Apart from these, it also contains significant amount of water. Preferably, water acts as carrier for said ingredients and helps in forming a homogenous composition. It also helps in providing a rheology suitable for dosing and applying the composition easily on the surfaces to be cleaned. However, high water content makes the product bulky. Thus, packaging of the product requires substantial amount of materials, such as, polyethylene, polyethylene terephthalate etc. The packaging materials are often sourced from non-renewable resources. In this regard there are continuous efforts to reduce such consumptions.

One of the ways to reduce such consumptions, is to have a product in concentrated format. A consumer is expected to dilute such product in water to form a liquid detergent and store it in a container. Such products are often termed as ‘Do it Yourself’ or abbreviated as ‘DiY’, which implies that a consumer prepare their own detergent from a precursor/concentrate by diluting it in water. Further, in-use, the consumer doses an aliquot of the liquid detergent into to a bucket/bowl of water or in tub of a washing machine forming a wash liquor and use it for washing. Thus, same product may be available in three forms, namely, concentrate, liquid detergent and wash liquor depending on extent of dilution. Typically, they vary in detersive content. Moreover, they differ in attribute and functionality. For example, wash liquor typically lowest in detersive active content among the forms, has viscosity like water and used immediately after preparation. On other hand, liquid detergent has attributes, such as, efficacy, appearance, sensory, stability etc., and they are supposed to be stored in a container for later use. It is expected that those attributes are such that consumers may relates the liquid detergent to conventional liquid detergents available in market.

Viscosity of liquid products is one of the key attributes. It can be correlated to pourability of the product. It also often relates to sensory of the product. For example, consumers relate high viscosity to high amount of detersive agent in the product, which drives manufactures to provide liquid detergents in viscous form. Thus, it is desired that the liquid detergent formed on dilution of a ‘DiY’ product has viscosity such that a consumer can relate it with conventional liquid detergents available in market.

One of the challenges of developing concentrated liquid products is to achieve desired viscosity of the liquid detergent formed on dilution. Typically, the viscosity of concentrated products drops with dilution in water resulting in low viscous liquid. This may not be preferred by consumers. It is possible to formulate a concentrated product with significantly high viscosity by adding a thickener such that when diluted it provides a viscous liquid detergent similar to conventional liquid detergent. However, such concentrated products face pourability issue and may not be liked by consumers either.

In this context, WO 2014/173659 A1 describes a fluid cleaning composition comprising: (a) a surfactant combination comprising: (i) a synthetic surfactant; and (ii) a glycolipid biosurfactant which is present at a level in the range 10 to 95 %wt. of the total surfactant in said surfactant combination, and (b) a benefit agent suspended in said fluid cleaning composition characterised in that the benefit agent comprises an encapsulate.

WO 2020/126592 A1 relates to a liquid detergent composition comprising (a) from 8 to 30 %wt. of a surfactant system comprising: (i) a primary surfactant of the formula R1-(OR')n-O-SO3 -M+, wherein: R1 is saturated or unsaturated C8 to C16 alkyl chain; R' is ethylene; n is from 1 to 18; M+ is a suitable cation which provides charge neutrality selected from sodium, calcium, potassium and magnesium; and (ii) at least one secondary surfactant selected from amphoteric surfactants, alkyl sulphates, alkylbenzene sulphonate and derivatives; (b) from 0.001 to 0.2 wt percent of polyethylene oxide having molecular weight higher than 200,000 g/mol, (c) from 0.05 to 2 %wt. of fatty acids comprising a saturated hydroxy fatty acids having 8 to 18 carbon atoms, saturated non-hydroxy fatty acids having 8 to 18 carbon atoms, or mixtures thereof; (d) 0.1 to 5 percent by weight of an inorganic salt selected from the group consisting of sodium chloride, magnesium sulphate, sodium sulphate and combinations thereof; and (e) water. DE 19648439 discloses use of mixture glycolipid and surfactants for manufacturing manual dishwashing detergent.

Instead of the prior arts, there is a need for an improved concentrated cleaning composition for providing a liquid detergent on dilution in water. It is desired that the concentrated composition has easy pourability, yet on dilution provides a liquid detergent matching one or more attributes of conventional liquid detergents.

Surprisingly, the present inventors have found that a concentrated cleaning composition comprising a combination of a rhamnolipid, a hydrotrope and a water-soluble inorganic salt provides a liquid detergent on dilution, which have a viscosity similar to that of the conventional liquid detergents.

Summary of the invention

In a first aspect the present invention provides a concentrated liquid cleaning composition for forming a liquid detergent on dilution in water comprising: a) 10 to 50 wt% of an anionic surfactant selected from alkyl sulphate, alkyl ether sulphate, alkyl benzene sulphonate and combinations thereof; b) 1 to 10 wt% of an amphoteric surfactant; c) 1 to 20 wt% of a rhamnolipid; d) 1 to 10 wt% of a hydrotrope; and e) 0.1 to 15 wt% of a water-soluble inorganic salt, wherein the composition has a viscosity in the range 300 to 800 mPa.s and when diluted in water in 1:4 ratio by weight has a viscosity at least 1000 mPa.S at 20 S'¹ shear rate, 25°C, wherein the pH of the composition is in the range from 4 to 7, wherein the ratio of rhamnolipid to hydrotrope is in the range 1:1 to 6:1 by weight.

In another aspect, the present invention provides a unit dose product for forming a liquid detergent on dissolution in water comprising a composition according to the first aspect contained in a water-soluble pouch.

In another aspect, the present invention provides a liquid detergent obtained by diluting a concentrated liquid composition according to the first aspect in water, wherein the liquid detergent has a viscosity in the range 1000 mPa.S to 2500 mPa.S at 20 S-1 shear rate, 25°C. In another aspect, the present invention provides a process for making a liquid detergent comprising steps of diluting a composition according to the first aspect in water; wherein the ratio of the composition to water is in range 1 : 1 to 1 : 10 by weight.

Detailed description of the invention

Any feature of one aspect of the present invention may be utilized 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. 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 " x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "x to y", it is understood that all ranges combining the different endpoints are also contemplated. Unless specified otherwise, amounts as used herein are expressed in percentage by weight based on total weight of the composition and is abbreviated as “wt%”. The use of any and all examples or exemplary language e.g. “such as” provided herein is intended merely to better illuminate the invention and does not in any way limit the scope of the invention otherwise claimed. Room temperature is defined as a temperature of about 25° Celsius.

According to the present invention there is provided a concentrated composition for forming a liquid detergent on dilution in water. The composition comprises: a) 10 to 50 wt% of an anionic surfactant selected from alkyl sulphate, alkyl ether sulphate, alkyl benzene sulphonate and combinations thereof; b) 1 to 10 wt% of an amphoteric surfactant; c) 1 to 20 wt% of a rhamnolipid; d) 1 to 10 wt% of a hydrotrope; and e) 0.1 to 15 wt% of a water-soluble inorganic salt, wherein the composition has a viscosity in the range 300 to 800 mPa.s and when diluted in water in 1:4 ratio by weight has a viscosity at least 1000 mPa.s at 20 S-1 shear rate, 25°C, wherein the pH of the composition is in the range from 4 to 7, wherein the ratio of rhamnolipid to hydrotrope is in the range 1 :1 to 6:1 by weight. Anionic surfactant

The composition comprises anionic surfactant. The anionic surfactant is selected form alkyl sulphate, alky ether sulphate, alkyl benzene sulphonate and combinations thereof.

The anionic surfactant may comprise alkyl ether sulphate having formula:

(Ri-(OR’)_n-O-SO₃’)x M^x+, wherein:

Ri is saturated or unsaturated Cs to Ci6, preferably C12 to C14 alkyl chain; preferably, R1 is a saturated Csto C16, more preferably a saturated C12 to C14 alkyl chain; R’ is ethylene; n is from 1 to 18; preferably from 1 to 15, more preferably from 1 to 10, still more preferably from 1 to 5; x is 1 or 2.

M^x+ is a suitable cation which provides charge neutrality, preferably sodium, calcium, potassium, or magnesium, more preferably a sodium cation. Organic counterions such as monoisopropylamine (MIPA), monoisopropanolamine, triisopropanolamine, ammonium, monoethanolamine, (MEA), diethanolamine (DEA), and triethanolamine (TEA) may also be employed.

Preferably the alkyl ether sulphate comprises 1 to 18, more preferably 1 to 15, even more preferably 1 to 10, yet more preferably 1 to 5 and most preferably 1 to 3 ethylene oxide units per molecule.

Preferred alkyl ether sulphate is sodium lauryl ether sulphate having 1 to 3 ethylene oxide units per molecule, more preferred sodium lauryl ether sulphate having 1 to 2 ethylene oxide units per molecule.

Preferably the anionic surfactant comprises alkyl sulphate. Preferably the alkyl sulphate is primary or secondary alkyl sulphate having C10 to C18 alkyl chain. Examples of alkyl sulphates include sodium lauryl sulphate, ammonium lauryl sulphate, diethanolamine (DEA) lauryl sulphate.

Suitable examples also include alkyl sulphates commercially available from natural source with trade names Galaxy 689, Galaxy 780, Galaxy 789, Galaxy 799 SP and from synthetic origin with trade names Safol 23, Dobanol 23A or 23S, Lial 123 S, Alfol 1412S, Empicol LC3, Empicol 075SR. Oher anionic surfactant suitable for the invention includes alkylbenzene sulphonates, particularly linear alkylbenzene sulfonates (LAS) with an alkyl chain length of from 10 to 18 carbon atoms. Commercial LAS is a mixture of closely related isomers and homologues alkyl chain homologues, each containing an aromatic ring sulfonated at the “para” position and attached to a linear alkyl chain at any position except the terminal carbons. The linear alkyl chain typically has a chain length of from 11 to 15 carbon atoms, with the predominant materials having a chain length of about C12. Each alkyl chain homologue consists of a mixture of all the possible sulpho-phenyl isomers except for the 1 -phenyl isomer. LAS is normally formulated into compositions in acid (i.e. , HLAS) form and then at least partially neutralized in-situ with a counterion. Suitable counterions are alkali metal ions, such as sodium, calcium etc. Organic counterions such as monoisopropylamine (MIPA), monoisopropanolamine, triisopropanolamine ammonium, monoethanolamine, (MEA), diethanolamine (DEA), and triethanolamine (TEA) may also be employed.

Alkylbenzene sulphonates and derivatives include water-soluble alkali metal salts of organic sulphonates having alkyl radicals typically containing from about 8 to about 22 carbon atoms, preferably 8 to 18 carbon atoms, still more preferably 12 to 15 carbon atoms and may be unsaturated.

Examples of other sulphonate based anionic surfactants suitable for the invention include sodium salt of linear alkylbenzene sulphonate, alkyl toluene sulphonate, alkyl xylene sulphonate, alkyl phenol sulphonate, alkyl naphthalene-sulphonate, ammonium diamylnaphthalene-sulphonate and sodium dinonylnaphthalene-sulphonate and mixtures with olefin sulphonates.

The composition comprises 10 to 50 wt% of the anionic surfactant. Preferably the composition comprises 12 to 48 wt%, more preferably 15 to 45 wt%, most preferably 20 to 40 wt% of the anionic surfactant.

Amphoteric surfactant

The composition comprises an amphoteric surfactant. Amphoteric surfactant suitable for the invention includes alkyl amine oxides, alkyl betaines, alkyl amidopropyl betaines, alkyl sulphobetaines (sultaines), alkyl glycinates, alkyl carboxyglycinates, alkyl amphopropionates, alkylamphoglycinates alkyl amidopropyl hydroxysultaines, acyl taurates and acyl glutamates, wherein the alkyl and acyl groups have from 8 to 19 carbon atoms. Examples include lauryl amine oxide, cocodimethyl sulphopropyl betaine and preferably lauryl betaine, cocam idopropyl betaine and sodium cocamphopropionate

Preferably the amphoteric surfactant is selected from cocoam idopropyl betaine (CAPB), coco amido propyl amine oxide (CAPAO), cocodiethanol amide (CDEA) and cocomonoethanol amide (CMEA), and combination thereof. Most preferred amphoteric surfactant is cocoam idopropyl betaine (CAPB).

The composition comprises 1 to 10 wt% of the amphoteric surfactant. Preferably the composition comprises 2 to 9 wt%, more preferably 2.5 to 8 wt%, and most preferably 3 to 7.5 wt% of the amphoteric surfactant.

Preferably, the ratio of amphoteric surfactant to the anionic surfactant 1:10 to 1 :3, preferably 1 :8 to 1 :5 by weight.

Rhamnolipid

The composition comprises a rhamnolipid. Rhamnolipids are a class of glycolipid, preferably obtained from the strain of bacteria Pseudomonas aeruginosa, thus often it refers as biosurfactant. Typically, it contains a rhamnose moiety with a fatty acid tail.

Rhamnolipid in combination with the hydrotrope in the composition provide desired viscosity profile in concentrated form as well as in the liquid detergent formed on dilution.

More details about rhamnolipids may be found in Applied Microbiology and Biotechnology (2010) 86:1323-1336 by E. Deziel et al. Rhamnolipids may be obtained commercially from suppliers such as, Glycosurf, AGAE Technologies and Urumqi Unite Bio-Technology Co., Ltd.

The rhamnolipid in the present context includes mono-rhamnolipids and di-rhamnolipids.

Mono-rhamnolipids contain one rhamnose moiety. A typical mono-rhamnolipid produced by P. aeruginosa is L-rhamnosyl-p-hydroxydecanoyl-p-hydroxydecanoate (RhaC10C10). It may be referred to as Rha-C10-C10, with a formula of C26H48O9. The IUPAC Name is 3-[3- [(2R,3R,4R,5R,6S)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxydecanoyloxy] decanoic acid, wherein ‘Rha’ refers to a rhamnose moiety. Di-rhamnolipids contains two rhamnose moieties. A typical di-rhamnolipid is L-rhamnosyl-L- rhamnosyl-p-hydroxydecanoyl-p-hydroxydecanoate (Rha2C10C10). It may be referred to as Rha-Rha-C10-C10, with a formula of C32H58O13. The IIIPAC name is 3-[3-[4,5-dihydroxy-6- methyl-3-(3,4, 5-tri hyd roxy-6-m ethyloxan-2-yl)oxyoxan-2-yl]oxyd ecanoyloxy]decanoic acid, wherein ‘Rha’ refers to a rhamnose moiety.

Examples of rhamnolipids suitable for the invention include:

Rhamnolipids produced by P. aeruginosa (mono-rhamnolipids):

Rha-C8-C10, Rha-C10-C8, Rha-C10-C10, Rha-C10-C12, Rha-C10-C12:1, Rha-C12-C10, Rha- C12:1-C10

Rhamnolipids produced by P. aeruginosa (di-rhamnolipids):

Rha-Rha-C8-C10, Rha-Rha-C8-C12:1 , Rha-Rha-C10-C8, Rha-Rha-C10-C10, Rha-Rha-C10- C12:1 , Rha- Rha-C-10-C-12, Rha-Rha-C-12-C-10, Rha-Rha-C-12:1-C-12, Rha-Rha-C-10- C14:1

Rhamnolipids produced by P. aeruginosa (unidentified as either mono- or di-rhamnolipids): C8- C8, C8-C10, C10-C8, C8-C12:1 , C12: 1-C8, C10-C10, C12-C10, C12:1-C10 C12-C12, C12: 1- C12, C14-C10, C14:1-C10, C14-C14.

Rhamnolipids produced by P. chlororaphis (mono-rhamnolipids only): Rha-C10-C 8, Rha-C10 - C10, Rha-C12-C10, Rha-C12:1-C10, Rha-C12-C12, Rha-C12: 1-C12, Rha-C14-C10. Rha-C- 14:1-010.

Rhamnolipids produced by Burkholdera pseudomallei (di-rhamnolipids only): Rha-Rha-C14- C14.

Rhamnolipids produced by Burkholdera plantarii (Pseudomonas) (di-rhamnolipids only): Rha- Rha-C14-C14.

Preferably the rhamnolipid is a di-rhamnolipid of formula: Rha2-C8-12-C8-12. The preferred alkyl chain length is from C8 to C12. The alkyl chain may be saturated or unsaturated. The composition comprises 1 to 20 wt.% of the rhamnolipid. Preferably the composition comprises 1.5 to 18 wt%, more preferably 2 to 16 wt%, even more preferably 2.5 to 14 wt% and most preferably 3 to 12 wt% of the rhamnolipid.

Preferably the ratio of anionic surfactant to the rhamnolipid is in the range from 1 :1 to 10:1 , more preferably 1 :1 to 9:1 and most preferably 1:1 to 8:1 by weight.

The composition comprises a hydrotrope. Hydrotrope are typically low molecular weight, water- soluble or water-miscible organic liquids. Examples of hydrotrope suitable for the invention included C1 to C5 monohydric alcohols e.g., ethanol, n propanol, isopropanol etc.; C2 to C6 diols e.g., monopropylene glycol and dipropylene glycol; C3 to C9 triols e.g., glycerol; polyethylene glycols having a weight average molecular weight in the range from about 200 to 600; C1 to C3 alkanolamines e.g., monoethanolamine, diethanolamine and triethanolamines. The most preferred hydrotrope is polyethylene glycol.

The composition comprises 1 to 10 wt% hydrotrope. Preferably the composition comprises 1.5 to 9 wt%, more preferably 2 to 8 wt% and most preferably 2.5 to 7 wt% of the hydrotrope.

Rhamnolipid in combination with the hydrotrope and the water-soluble inorganic salt in the composition provide desired viscosity profile in composition as well as in the liquid detergent formed on dilution. It is found the combination helps in reconstituting the viscosity of the liquid detergent forming on dilution in water.

The ratio of rhamnolipid to the hydrotrope is in the range from 1:1 to 6:1 , more preferably 1:1 to 5:1, even more preferably 1 :1 to 4: 1 and most preferably 1 :1 to 3: 1 by weight.

Inorganic salts

The composition comprises 0.1 to 15 wt% of a water-soluble inorganic salt. Preferably the inorganic salt is a monovalent or divalent salt of chloride or sulphate. Preferably the inorganic salt is selected from sodium chloride, sodium sulphate, potassium chloride, magnesium sulphate and combinations thereof. Preferably the inorganic salt is sodium or potassium salt of chloride or sulphate or combinations thereof. It is observed that a combination of the rhamnolipid, the hydrotrope and the water-soluble inorganic salt provides desired viscosity of the cleaning composition, as well as reconstitute viscosity on dilution in water thereby providing a viscosity similar to the conventional liquid detergent.

More preferably, the composition comprises 0.5 to 12 wt%, most preferably 1 to 10 wt% of the inorganic salt.

Viscosity of the composition

The composition is concentrated liquid composition. It is diluted in water to form a liquid detergent having one or more attributes similar the conventional liquid detergents available in market. Viscosity is one of such attributes.

The composition has different viscosity profile in neat form and diluted detergent. The term ‘neat’ herein refers to the composition as it is and used here to distinguish the diluted liquid detergent from it.

The composition has a viscosity in the range 300 to 800 mPa.S at 20 S'¹ shear rate and 25°C with cone geometry. It is observed that such viscosity range provide ease of pouring from the container. More preferably the viscosity of the composition is in the range 350 to 750 mPa.S, even more preferably 400 to 700 mPa.S and most preferably 450 to 650 mPa.S at 20 S'¹ shear rate and 25°C in cone geometry (plate type rheometer)

Typically, viscosity of a conventional liquid detergent reduces on dilution in water. In the present invention, surprisingly it is found that a combination of the rhamnolipid, the hydrotrope and the water-soluble inorganic salt in the concentrated composition reconstitute viscosity in dilution and provide a liquid detergent.

The diluted liquid detergent has a viscosity in at least 1000 at 20 S'¹ shear rate and 25°C with cone geometry, when diluted at a ratio 1 :4 by weight in water. Preferably the diluted liquid detergent has a viscosity in the range 1000 to 2500 mPa.S, more preferably 1050 to 2000 mPa.S, even more preferably 1100 to 1800 mPa.S and most preferably 1100 to 1500 mPa.S at 20 S'¹ shear rate and 25°C with cone geometry ( plate type rheometer), when diluted at a ratio 1 :4 by weight in water at 20 S'¹ shear rate and 25°C, at dilution said above. The ratio mentioned in previous paragraph is an indicative within the scope of the invention and used here to clearly define the feature. It nowhere limits the scope of the claim to the particular number. pH of the composition

The composition has a pH in the range from 4 to 7. Preferably the pH of the composition is in the range from 4.5 to 6.5, more preferably 5 to 6. Preferably the composition comprises an organic acid or it’s salt for adjusting the pH of the composition.

Water

The composition may comprise water. Preferably the composition comprises 5 to 70 wt% water. The composition according to the present invention preferably is in concentred format, thus lesser the amount of water is preferable. More preferably the composition comprises 10 to 65 wt%, even more preferably 15 to 60 wt%, and most preferably 20 to 55 wt% of water. Preferably the amount of water includes the water added in processing of the composition, as well as the water present in the raw materials in solution or dispersion form.

Other Ingredients

The composition may further comprise other ingredients which aid in the cleaning, sensory or product performance. Compositions may contain various optional ingredients such as additional surfactants, thickeners, colorants, preservatives, polymers, anti-microbial agents, perfumes, pH adjusters, enzyme, antifoaming agents, sequestrants etc. based on the application.

The composition may further comprise a non-ionic surfactant. Examples of suitable non-ionic surfactant include the condensation products of a higher alcohol (e.g., an alkanol containing about 8 to 18 carbon atoms in a straight or branched chain configuration) condensed with about 5 to 30 moles of ethylene oxide, for example, lauryl or myristyl alcohol condensed with about 16 moles of ethylene oxide (EO), tridecanol condensed with about 6 moles of EO, myristyl alcohol condensed with about 10 moles of EO per mole of myristyl alcohol, the condensation product of EO with a cut of coconut fatty alcohol containing a mixture of fatty alcohols with alkyl chains varying from 10 to about 14 carbon atoms in length and wherein the condensate contains either about 6 moles of EO per mole of total alcohol or about 9 moles of EO per mole of alcohol and tallow alcohol ethoxylates containing 6 EO to 11 EO per mole of alcohol. Particularly preferred is Lauryl alcohol condensed with 5, 7 and 9 moles of ethylene oxide (Laureth 5, Laureth 7 and Laureth 9). Condensates of 2 to 30 moles of ethylene oxide with sorbitan mono- and tri-C10- C20 alkanoic acid esters having a HLB of 8 to 15 also may be employed as the non-ionic surfactant.

Application

The composition is a concentrated liquid composition and may fall under the purview of ‘Do it Yourself’ or ‘DiY’ products, which implies that a consumer prepares their own detergent from a precursor/concentrate by diluting it in a particular ratio. The consumer store the liquid detergent in a container and use it as and when required.

In one aspect, the present invention provides a unit dose product for forming a liquid detergent on dissolution in water comprising a composition according to the invention contained in a water-soluble pouch. ‘Unit dose’ herein refers to a pre-defined amount of a composition suitable for single. In case of unit dose products, a consumer may not need to adjudge the dose of the composition. In present scenario, the composition in unit dose format may be packaged with a water-soluble film, such that, the consumer directly doses the product in a container and add a known amount of water. Preferably the amount of water is mentioned on the pack of the product or may be provided as set of instructions. Preferably the water-soluble film made of a water- soluble polymer. Examples of polymer suitable for forming the water-soluble film include polyvinyl alcohol, polyacrylates, water-soluble acrylate copolymers, polyvinyl pyrrolidone, polyethyleneimine, pullulan, water-soluble natural polymers including, starch and its derivatives.

It may also be possible to provide the composition filled in a container with sufficient empty space. A consumer is expected to add water in the container up to a pre-set level and form the liquid detergent at their ease. In such cases, the container may be made of polymeric materials suitable for packaging application. Examples of suitable polymers include polyesters, polyolefins, polyamides, polystyrene (PS), polyanhydrides, polyacrylates, poly hydroxy alkanoates, poly vinyl chloride, thermoplastic polyurethanes, polycarbonate (PC), polylactic acid (PLA), acrylonitrile/butadiene/styrene copolymer (ABS), styrene/acrylonitrile copolymer (SAN), polyoxymethylene (POM), biodegradable thermoplastics, starch-based thermoplastics, their derivatives, and combination thereof.

The composition of the present invention may be formulated for hard surface cleaning application and forms a hard surface cleaning detergent on dilution in water. Hard surface cleaning generally encompasses cleaning surfaces such as, kitchen utensils, dishes, kitchen platform, tabletop etc. Dishwashing detergents are typically used for cleaning dishes and kitchen utensils. Dishwashing includes machine dishwashing and hand dishwashing.

Preferably the dishwash composition in addition to the said ingredients further comprises builders, fragrances, polymers, colorants, thickener etc.

The dishwash composition intended for machine dishwash, may further comprise an antifoaming agent. Examples of suitable antifoaming agents include silicones, fatty acids. Preferably, the fatty acid, if present, is selected from a group comprising caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, 12-hydroxy stearic acid and mixture thereof.

In another scenario, the composition may be formulated for laundering and forms a laundry detergent on dilution. The term “laundering” herein refers to treating or washing fabrics. In such cases, the composition may further comprise other ingredients such as, builders, sequestrants, soil release polymers, perfume, enzyme, fluorescer. preservative etc.

In one aspect there is provided a liquid detergent obtained by diluting the concentrated liquid cleaning composition in water, wherein the liquid detergent has a viscosity in the range 1000 mPa.S to 2500 mPa.S at 20 S'¹ shear rate, 25°C. Preferably the liquid detergent has a viscosity in the range 1050 to 2000 mPa.S, more preferably 1100 to 1800 mPa.S and most preferably 1100 to 1500 mPa.S at 20 S'¹ shear rate and 25°C, when measured in plate type rheometer with cone geometry. The liquid detergent may be obtained by diluting in a ratio 1 :1 to 1 :10, more preferably 1 :1 to 1 :8, even more preferably 1 :1 to 1 :7 and most preferably 1 :1 to 1 :5 by weight.

According to the present invention, there is provided a process for making a liquid detergent comprising steps of diluting the composition in water; wherein the ratio of the composition to water is in range 1 :1 to 1 :10 by weight. More preferably the ratio of the composition to water is in the range 1 :1 to 1 :8, even more preferably 1 :1 to 1 :7 and most preferably 1 :1 to 1 :5 by weight.

The invention will now be illustrated by means of the following non-limiting examples. Examples

Following materials were used in the examples to prepare various compositions:

Table 1 Ex 1 to 3 and A to E were prepared according to the recipes shown in table 2. Ex

Ex 1 to 3 are within the scope of the present invention and Examples A to E are control examples (outside the scope of the present invention).

Table 2

Viscosity of each composition were evaluated in two forms, namely, neat and diluted in water in 1 :4 ratio by weight. The term ‘neat’ herein refers to the composition used as is without dilution. Viscosity of the compositions were measured using Modular Compact Rheometer, model number MCR 302 available with Rheocompass software from Anton Paar GmbH with plate type geometry, at 20 S'¹ shear rate and 25°C with CP50 geometry. The results are summarized below:

Table 3 According to table 3, it is evident that Ex 1 to 3 provide desired viscosity profile in neat as well as in diluted detergent. Whereas Ex A to E provide relatively high viscosity at neat, which may not be desired. Further, Ex A to E ether fail to reconstitute viscosity or does not build significant viscosity on dilution. Ratio of rhamnolipid and hydrotrope

Ex F, G were prepared according to the recipe shown in table 4 to evaluate the effect of relative amount (ratio) of the rhamnolipid to hydrotrope. Ex 1 is already described earlier. Ex F and G are comparative examples (outside the scope of the present invention).

Table 4

Viscosity of each composition were evaluated in two forms, namely, neat and diluted in water in 1 :4 ratio by weight. The term ‘neat’ herein refers to the composition used as is without dilution. Viscosity of the compositions were measured using Modular Compact Rheometer, model number MCR 302 available with Rheocompass software from Anton Paar GmbH with plate type geometry, at 20 S-1 shear rate and 25°C with CP50 geometry. The results are summarized below:

Table 5

According to table 4 and 5, Ex 1 provides the desired viscosity profile for both neat and diluted detergent, whereas Ex- F and G provide very high viscosity in neat form. Further Ex-F does not reconstitute viscosity on dilution, and Ex-G is failed to achieve the desired viscosity value, thus may not be suitable for the invention.

Example according to the prior art document (DE 196 48439 A1)

Ex- H is an example as disclosed in the prior art document (example 6 of DE 19648 439 A1). Viscosity was measured following the method described above.

Table 6

Ex-H seem to be water thin liquid having a viscosity of 20 mPa.S at 20 S-1 shear rate and 25°C with CP50 geometry, which is far below compared to Ex-1 (according to the present invention).

Claims

1 . A concentrated liquid cleaning composition for forming a liquid detergent on dilution in water comprising: a) 10 to 50 wt% of an anionic surfactant selected from alkyl sulphate, alkyl ether sulphate, alkyl benzene sulphonate and combinations thereof; b) 1 to 10 wt% of an amphoteric surfactant; c) 1 to 20 wt% of a rhamnolipid; d) 1 to 10 wt% of a hydrotrope; and e) 0.1 to 15 wt% of a water-soluble inorganic salt, wherein the composition has a viscosity in the range 300 to 800 mPa.s and when diluted in water in 1 :4 ratio by weight has a viscosity at least 1000 mPa.s at 20 S'¹ shear rate, 25°C, wherein the pH of the composition is in the range from 4 to 7, wherein the ratio of rhamnolipid to hydrotrope is in the range from 1 :1 to 6:1 by weight,

2. A composition as claimed in claim 1 wherein the anionic surfactant is selected from alkyl ether sulphate, primary alkyl sulphate and combinations thereof.

3. A composition as claimed in claim 1 or 2 wherein the anionic surfactant is sodium lauryl ether sulphate having 1 to 3 ethylene oxide unit per molecule.

4. A composition as claimed in any one of claims 1 to 3 wherein the amphoteric surfactant is selected from alkyl amine oxides, alkyl betaines, alkyl amido propyl betaines, alkyl sulpho-betaines, and combinations thereof.

5. A composition as claimed in claim 4 wherein the amphoteric surfactant is coco- amido propyl betaine.

6. A composition as claimed in any one of claims 1 to 5 wherein the ratio of anionic surfactant to rhamnolipid is in the range 1 :1 to 10:1 by weight.

7. A composition as claimed in any one of claims 1 to 6 wherein the hydrotrope is selected from mono-propylene glycol, di-propylene glycol, polyethylene glycol and combinations thereof. A composition as claimed in claim 7 wherein the hydrotrope is polyethylene glycol. A composition as claimed in any one of claims 1 to 8 comprising 0.5 to 12 wt% of a water-soluble inorganic salt. A composition as claimed in any one of claims 1 to 9 wherein the inorganic salt is selected from sodium chloride, sodium sulphate, magnesium sulphate and combinations thereof. A unit dose product for forming a liquid detergent on dissolution in water comprising a composition as claimed in any one of claims 1 to 11 contained in a water-soluble pouch. A liquid detergent obtained by diluting a concentrated liquid composition as claimed in any one of claims 1 to 10 in water, wherein the liquid detergent has a viscosity in the range 1000 mPa.S to 2500 mPa.S at 20 S'¹ shear rate, 25°C. A liquid detergent as claimed in claim 12 wherein the ratio of the composition to water is in the range 1 : 1 to 1 : 10 by weight. A process for making a liquid detergent comprising steps of diluting a composition as claimed in any one of claims 1 to 10 in water; wherein the ratio of the composition to water is in range 1 : 1 to 1 : 10 by weight.