Title of Invention

CLEANING COMPOSITION

Abstract A cleaning composition comprising an immiscible liquid system having at least one liquid-liquid interface with an interfacial tension greater than 5mN/m, I characterized i in that the less polar solvent in the system has a carbon chain length of at least 4.
Full Text FORM -2
THE PATENTS ACT, 1970 (39 of 1970)
COMPLETE SPECIFICATION
(See Section 10)
CLEANING COMPOSITIONS
HINDUSTAN LEVER LIMITED, a company incorporated under the Indian Companies Act, 1913 and having its registered office at Hindustan Lever House, 165/166, Backbay Reclamation, Mumbai -400 020, Maharashtra, India
The following specification particularly describes the nature of the invention (and the manner in which it is to be performed.


20-1-2004

Technical field:
T"he invention relates to a cleaning/washing composition comprising a non-toxic and safe system of immiscible liquids with high interfacial tension which does not require the use of additional detergency benefit agents, and to an improved process/method of cleaning/washing fabric using the same.
Background and prior art:
Conventionally, fabric is cleaned using water and a detergent surfactant system which is known as wet cleaning. Surfactants adsorb on both fabric and soil and thereby reduce the respective interfacial energies and this facilitates removal of soil from the fabric. Alternatively, it is done by a process called dry cleaning where in organic solvents such as perchloroethylene (PCE), petroleum based or Stoddard solvents, chlorofluoro carbon (CFC)-113 and 1,1,1-trichloroethane are used, all of which are generally aided by a surfactant. The organic solvent helps in the removal of oily soil in the presence of detergents. Soil removal can be achieved by a small reduction in interfacial tension. The particulate soil is largely removed by providing agitation.
The organic solvents used for cleaning are generally toxic and also pose a problem as they are inflammable, creating potential fire hazards. Another major concern in solvent cleaning is the tendency of vapour loss from the cleaning system into the atmosphere especially when they are used at elevated temperatures. Solvent cleaning processes generally employ chlorinated solvents that are linked to ozone depletion. Several attempts have been made to avoid these problems and to find suitable substitutes.
WO-A-0036206 (3M) discloses dry cleaning compositions comprising hydrofluoroethers along with other co-solvents, and water present in an amount of less than 1% by weight of the composition. Hydrofluoroethers are relatively safe and less aggressive towards fabric.
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US-A-6228826 (MiCell Tech.Inc.,) discloses the use of end-functionalized polysiloxane surfactants to enhance the dry-cleaning aspects of carbon dioxide which was earlier considered as an alternative to the potentially toxic halocarbon solvents.
Regardless of the type of solvent used, which may be water or organic, agitation of garments in the cleaning medium is essential to accelerate the removal of the soluble soil or the insoluble, particulate soil. During dry cleaning when a surfactant is used, a maximum of about 10% of water is also used along with the solvent system in order to facilitate the removal of water soluble stains.
Our earlier-filed co-pending application 469/mum/2000 dated 23/5/2000, equivalent to WO-A-01/90474, published on 29 November 2001, discloses a process of cleaning fabric using the liquid-liquid interface of at least two immiscible liquid phases with an interfacial tension greater than 5mN/m, under agitation. Even in this method of cleaning the solvents "used could be toxic, inflammable and have an impact on the environment. In our co-pending application No.1000/MUM/2001 dated 12/10/2001 it is described and claimed that a cleaning composition comprising an immiscible liquid system having at least one liquid-liquid interface with an interfacial tension greater than 5mN/m, the less polar solvent in the system being a silicon with more than 3 SiO units, characterized in that the composition comprises from 0.001-20% of one or more benefit agents which are soluble in at least one of the phases of the liquid system.
In our co-pending application No. 1001/MUM/2001 dated 12/10/2001 it is described and claimed that a cleaning composition comprising an immiscible liquid system having at least one liquid-liquid interface with an interfacial tension greater than 5 mN/m, characterised in that the composition has a pH of above 7.
Summary Of The Invention
It has now been found that if in the above-mentioned immiscible liquid phase the less polar solvent has a carbon chain length of at least 4 or is a silicone with more than 3 SiO units the above mentioned problems of toxicity, flammability and environmental impact
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can be circumvented whilst retaining superior cleaning of fabric. The system comprising the immiscible liquid phase is superior to pure solvent cleaning in terms of the detergency benefit.especially for particulate soil. Preferably the carbon chain length is greater than 6.
Brief description of the invention :
The applicants have found that efficient removal of both soluble and insoluble soils may be achieved by the cleaning of fabric under agitation using a washing/cleaning system comprising a liquid liquid interface of at least two immiscible liquid phases with an interfacial tension greater than 5mN/m, wherein the less polar solvent has a carbon
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chain length of at least 4 is a silicone with more than 3_SiO units. It is also found that superior cleaning may be achieved economically by the use of water as a major component along with the organic solvent with the use of little or no surfactant contrary to prior art which teaches use of water at levels not exceeding 10% together with the use of surfactants.
The applicants have developed a system with at least one immiscible phase and with high interfacial tension which provides superior cleaning.
Detailed description of the invention:
Thus according to one aspect of the present invention there is provided a
^yy QQ cjejinin^Awashing composition comprising an immiscible liquid system having an
interfacial tensionTBreaTer than 5mN/rrnwherein the less polar solvent has a carbon
chain length of atfleast4jor is a silicone with more than units.

Interfacial tension may be measured using various techniques, such as sessile drop, pendant drop, spinning drop, drop volume or Wilhelmy plate method. For the purposes of the present invention, interfacial tension is measured by the Wilhelmy plate method, using a Kruss Processor Tensiometer K12, at 25°C.
i c t\f!? For some systems, the interfacial tension may change whilst undergoing shearing
/
forces(typTcallyjencountered in a wash process. It is customary to refer to the interfacial tension under these conditions as a "dynamic interfacial tension" (DIFT) and may be measured by a maximum bubble pressure technique.
According to a preferred aspect the cleaning/washing composition comprises an
immiscible liquid system with an interfacial tension greater less polar solvent has a carbon chain length of ffi least4jor is a silicone with more than 3 SiO units and the concentration of the most polar liquid\|s 10.1-90% (v/v).


According to a more( aspect of the present invention the cleaning/washing composition comprises an immiscible liquid system with an interfacial, ;tensibn. than 20mN/m\vherein the less polar solvent has a carbon/Chain length.pf at least-ot is /
a silicone with more thanC3 SiO unitsiand selectively? provided ' that the '
concentration of the most polar liquid is 40-90% (v/v) for a period of at least 5 minutes
during the wash process.
y
It is preferred that the carbon chain length of the less polar solvent is greater than 6,)t
w_.
particularlymreater than 12jand more preferablygreater than 16. >
..J*.'



According to another aspect of the present invention there is provided a process of
cleaning fabric comprising agitating the fabric in the above disclosed immiscible liquid
— ■■ --- ..,..„-.. .„„„„__. ^_
.system having an interfacial tension than 5niN/m])wherein the less polar solvent has a carbon chain length of/at least4)or i



Solvents:

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The less polar solvents that have a carbon chain length of aTeast preferably reate?
an]6 may be selected from branched and linear alkanes (chemical formula CnH2n+2



where n isfat least 4) preferably greater than ,6), including but not limited to hexane,
heptane, octane, nonane, decane, dodecance, tridecane, tetradecane, pentadecane
etc. and mixtures thereof. Commercially available mixtures of this type include Isopar L
(C11-C15 alkanes - ex Exxon) and DF2000 (C11-C15 iso-alkanes; CAS#90622-58-5,ex
Exxon). They may also be selected from branched and linear alkenes with atjeast 4,
preferably more than 6 carbon atomsN including but not limited to octenes, nonenes,
decenes, undecenes, dodecenes etc, with one or more double bonds, and mixtures
thereof-
They may also be selected from ethers with at(Jeast 4 carbon atomi) including fluoroethers such as methoxy nonafluorobutane HFE-7100(i.e. C4F9-OCH3) and ethoxy

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nonafluorobutane HFE-7200(i.e. i;from esters with at least 4 carbon atoms,
such as dibutyl phthalate, dioctyl phthalate, C8-C24 saturated and/or unsaturated fatty acid methyl esters; and terpenes such as limonene; and mixtures of the above.
C8-C24 saturated and/or unsaturated fatty acid methyl esters are particularly preferred esters as less polar solvents, and typical examples thereof are C10-C18 fatty acid methyl esters such as methyl laurate, methyl myristate, methyl stearate, methyl linoleate, methyl linolenate etc., and mixtures thereof.
The less polar solvents with more than 3 SiO units may be selected from polydimethyl siloxane oils. Linear and cyclic siloxanes known as Lx and Dx where x is greater than three are suitable for use in the invention. Specific examples include octamethylcyclotetrasiloxane(D4) (ex-Dow Corning), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), decamethyltetrasiloxane (L4) and dodecamethyl pentasiloxane(L5).
;**.
The immiscible liquid system furthermore comprises at least one other, more polar
V fcf solvent such that the liquid system has an interfacial tension^reater than 5 mN/rrySuch
more polar solvent may be selected from water, alcohols, ketones, aromatic solvents,
halogenated solvents, heterocyclic compounds; and esters, and ethers with(jess than
carbon atoms. Preferably the more polar solvent is water.
OPTIONAL INGREDIENTS
It is possible to incorporate other conventional detergent ingredients such as surfactants, builders, anti-redeposition agents, soil release polymers, hydrotropes, enzymes, bleaches, fluorescers, perfumes etc. into the immiscible liquid system.
Agitation:
Agitation can be provided by impellers that cover the vertical flow profile or radial flow profile or a combination of both so that thorough mixing of the immiscible liquids take
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place. Agitation can be provided by impellers that are open curved turbine, turbine type propeller, axial flow turbine, flat blade turbine, inverted vane turbine; rnarine propeller etc. This action may also be accompanied by a tumbling action. Optionally agitation can also be provided by a combination of rotation and tumbling action, Other forms of agitation using gas jets or ultra sound may also be employed. Other forms of agitatiqn generally known in the art can also be employed provided it ensures a good'mixing of the immiscible liquid phases.
The nature of the invention, its objects and advantages will be more apparent from the ensuing description made with relation to non-limiting exemplary examples of the above identified various aspects of the invention.
The invention will now be described in greater detail with reference to immiscible liquid compositions for cleaning fabric.
EXAMPLES Example 1
Carbon soot N220, Carbot, (15 mg) was added to a 5 mg solution of sodium dodecyl sulphate in 100 ml of de-ionised water and the mixture dispersed evenly by sonication in arTultra-sound bath for a minimum of 1.5 hoursTjA swatch of plain white cotton fabric 10cm xlOcm (Poplin~weave, ex Hindustan Spinning & Weaving Mills, Mumbai) was then dipped into this mixture by hand until the cotton was observed visibly to be wetted completely - (10-20)s. The swatch was then withdrawn from the suspension, allowed to drain naturally and air dry overnight. This process was repeated with a further 2 swatches. The initial reflectance at 460nm (R460*), with contribution from ultra-violet radiation removed, was measured using a Macbeth Colour-eye 7000A reflectometer. The three swatches were placed into a 500 ml conical flask to which 300 ml of water + 0.75grams of detergent (Surf Excel ex-Hindustan Lever Ltd) had been added (2.5 grams per litre as per current consumer habit). The conical flask was agitated at 120rpm for 30 mins at ambient temperature
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using a reciprocating agitator, which facilitates efficient mixing of the liquids. Following washing, the individual swatches were air-dried and the final reflectance values for the swatches at 460nm with contribution from ultra-violet radiation removed, were determined. The change in reflectance AR is determined by subtracting the initial reflectance from the final reflectance and the average change in detergency, together with the standard deviation is presented in Table 1.
Example 2
The procedure outlined in Example 1 was repeated but with the water + detergent wash medium replaced with 300 ml of methoxy nonafluorobutane (tradename HFE 7100, ex-3M). The average change in reflectance values for this system is reported in Table 1.
Example 3
The procedure outlined in Example 1 was repeated but with the water + detergent wash medium replaced with 300 ml synthetic aliphatic hydrocarbon (DF-2000, ex-Exxon). The average change in reflectance values for this system is reported in Table 1.
Example 4
The procedure outlined in Example 1 was repeated but with the water + detergent wash medium replaced with 60ml of petroleum ether (from MERC chemicals) + 240 ml of deionised water. The average change in reflectance values for this system is reported in Table!
Example 5
The procedure outlined in Example 1 was repeated but with the water + detergent wash medium replaced with 60 ml mixture of methoxy nonafluorobutane (tradename HFE 7100, ex-3M) + 240ml of deionised water. The average change in reflectance values for this system is reported in Table 1.
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Example 11
The procedure outlined in Example 1 was repeated but with water + detergent wash medium replaced with 60ml of Fatty Acid Methyl Ester CE12lS'(a mixture of methyl laurate, methyl myristate & methyl stearate, ex-P&G, Malaysia, CA.-84-8) and 240 ml of water. The average change in reflectance values for this system is reported in Table 1.
Example 12
The procedure outlined in Example 1 was repeated but with water + detergent wash medium replaced with 60ml of Fatty Acid Methyl Ester C2170 (a mixture of methyl laurate, & methyl myristate, ex P & G Malaysia, CAS#67762-40-7) and 240 ml of water. The average change in reflectance values for this system is reported in Table 1.
Example 13
The procedure outlined in Example 1 was repeated but with water + detergent wash medium replaced with 60ml of Soya methyl ester (a mainly C18 unsaturated fatty acid methyl ester ex Columbus Foods, USA) and 240 ml of water. The average change in reflectance values for this system is reported in Table 1.
Example 14
The procedure outlined in Example 1 was repeated but with water + detergent wash medium replaced with 60ml Palm methyl ester (a methyl laurate; tradename Exceparl ML85 ex-Kao, Japan) and 240 ml of water. The average change in reflectance values for this system is reported in Table 1.
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The use of water alone as control gave a AR460* of 4.5.
The data presented in table 1 show that solvents like methoxy nonafluorobutane , synthetic aliphatic hydrocarbons and fatty acid methyl esters, that are safe, possess low flammability, low environmental toxicity, both in terms of biodegrability and ozone depletion potential, when used in combination with a high polar solvent such as water, gave a significantly higher detergency benefit in comparison to a regular detergent wash or the solvent alone. The benefit was comparable to the solvent: water system consisting of petroleum ether and water where petroleum ether, however, has the disadvantage of being inflammable(flash point 13°C). The combination of these solvents and water are capable of cleaning both particulate and oily soil from the fabric.
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WE CLAIM:
1. A cleaning composition comprising an immiscible liquid system having at least one
liquid-liquid interface with an interfacial tension greater than 5mN/m, I characterized
i in that the less polar solvent in the system has a carbon chain length of at least 4.
2. A composition as claimed in claim 1 wherein the less polar solvent has a carbon chain length, greater than 6.
3. A composition as claimed in claim 1 wherein the less polar solvent has a carbon chain length, greater than 12.
4. A composition as claimed in claim 1, wherein the less polar solvent has a carbon chain length, greater than 16.
5. A composition as claimed in anyone of claims 1 to 4 wherein the less polar solvent is a hydrocarbon.
A composition as claimed in claim 5 wherein the less polar solvent is a C11 - C15 hydrocarbon mixture.
7. A composition as claimed in anyone of claims 1 to 4 wherein the less polar solvent is methoxy or ethoxy nonafluorobutane.
8. A composition as claimed in anyone of claims 1 to 4 wherein the less polar solvent is a C8 - C24 saturated or unsaturated fatty acid methyl ester.
9. A composition as claimed in claim 8 wherein the less polar solvent is a C10 - C18 saturated or unsaturated fatty acid methyl ester.
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10. A composition as claimed in anyone of claims 1 to 9 wherein the interfacial tension is greater than l0mN/m.
11. A composition as claimed in anyone of claims 1 to 9 wherein the interfacial tension is greater than 20mN/m.
12. A composition as claimed in anyone of claims 1 to 11 wherein the concentration of the more polar liquid ranges from 10.1-90% (v/v).
13. A composition as claimed in claim 12 wherein the concentration of the more polar liquid ranges from 40-90% (v/v) for a period of at least 5 minutes when used in a cleaning process.
14. A composition as claimed in anyone of claims 1 to 13 wherein the more polar liquid is water.
Dated this 10th day of October 2002
Dr. Sanchita ganguli of S. Majumdar & co. Applicants' Agent

Documents:

999-mum-2001-cancelled pages(20-01-2004).pdf

999-mum-2001-claims(granted)- (20-01-2004).doc

999-mum-2001-claims(granted)- (20-01-2004).pdf

999-mum-2001-correspondence 1(15-03-2007).pdf

999-mum-2001-correspondence 2(10-10-2002).pdf

999-mum-2001-correspondence(ipo)-(12-03-2007).pdf

999-mum-2001-form 5(10-10-2002).pdf

999-mum-2001-form 1 (12-10-2001).pdf

999-mum-2001-form 19(23-06-2003).pdf

999-mum-2001-form 2(granted)- (20-01-2004).doc

999-mum-2001-form 2(granted)- (20-01-2004).pdf

999-mum-2001-form 3 (10-10-2002).pdf

999-mum-2001-petition under rule 138(12-07-2004).pdf

999-mum-2001-power of attorney(08-01-2003).pdf

999-mum-2001-power of attorney(12-07-2004).pdf


Patent Number 204815
Indian Patent Application Number 999/MUM/2001
PG Journal Number 25/2007
Publication Date 22-Jun-2007
Grant Date 12-Mar-2007
Date of Filing 12-Oct-2001
Name of Patentee HINDUSTAN UNILEVER LIMITED
Applicant Address 165/166, BACKBAY RECLAMATION, MUMBAI - 400 020, MAHARASHTRA,
Inventors:
# Inventor's Name Inventor's Address
1 DHANDAPANI KAVITHA 6/71, LINGARAJAPURAMB, BANGALORE-560 084, KAMATAKA,
2 BARGAJE VIJAYA MILIND #5, A.V. RESIDENCY, OFF. 80 FT. ROAD, BEHIND TATA INFOTECH, INDIRANAGAR, BANGLORE-560 066.
3 ROBERTS GLYN BUNGALOW NO. 2, BROOKEFIELDS, MARATHAHALLI POST, BANGALORE-560 037.
PCT International Classification Number C 121 D 7/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA