FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. TITLE OP THE INVENTION: "A Hand Dishwashing Liquid Detergent Composition Having Improved Low Temperature Stability"
2. APPLICANT
(a) NAME: GALAXY SURFACTANTS LTD.
(b)NATIONALITY: Indian Company incorporated under the Indian
Companies ACT, 1956
(c) ADDRESS: C-49/2, TTC Industrial Area, Pawne,
Navi Mumbai - 400703 Maharashtra, India
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
The present invention relates to a hand dishwashing liquid detergent composition having improved low temperature stability. Particularly, the invention relates to a hand dishwashing liquid detergent composition comprising N-Jong chain acyl neutral amino acid or its salt for improved low temperature stability. More particularly, the invention relates to a hand dishwashing liquid detergent composition comprising an effective amount of N-acyl sarcosine or N-acyl glycine or their salt or mixtures thereof for increased uniformity and prolonged low temperature stability.
BACKGROUND AND PRIOR ART OF THE INVENTION
Most conventional hand dishwashing liquid detergent compositions contain mixtures of various detersive surfactants. For examples various anionic surfactants such as fatty alkyl sulfates, fatty alkyl ether sulfates, various nonionic surfactants such as alkyl ethoxylates, alkyl polyglycosides and amphoteric surfactants such as fatty alkyl dimethyJ betaines, amidoalkyl dimethyl betaines, amine oxides, amidoamine oxides in order to remove a wide variety of soils and stains from surfaces. Combination of anionic surfactants such as fatty alkyl sulfates and amphoteric surfactants such as alkyl dimethyl amine oxides is considered to be a very good detergent mixture.
The hand dishwashing liquid detergent compositions comprising anionic and amphoteric surfactants known so far are stable, without undergoing any precipitation, haziness and separation, for around 2-3 hrs at 0°C. However, if it is stored for longer time than mentioned herein before, they turn hazy or precipitates or they undergo phase separation. This property of hand dishwashing liquid detergent compositions to succumb to low temperature environment is highly undesirable to customers. It is undesirable in terms of both performance and aesthetic point of view. A change of phase in low temperature results in a change in property of the detergent composition which in turn results in a poor

performance of the composition. Aesthetically also it does not attract the users. The approaches perused so far in the art do not solved the problem of low temperature stability of hand dishwashing liquid detergent compositions comprising anionic and amphoteric surfactants for prolonged period and that too maintaining an optimum viscosity.
US 6069122 relates to detergent compositions containing low molecular weight organic diamines for hand dishwashing which has improved grease removal performance and benefits in sudsing. The detergents of this invention also have improved low temperature stability properties and dissolution properties. The diamines of the US'122 in higher pH formulations (about 8.0-12) across a broad range of hardness (8 to >1,000 ppm) in combination with surfactants also provide sensory benefits by giving a silky feel to wash liquor and mildness to the skin.
US 6521577 relates to hand dish washing compositions comprising a low molecular weight organic diamine having a pKl and a pK2 value in the range of from 8 10 11.5, an anionic surfactant, an amine oxide, and magnesium ions, said magnesium being present at an equimolar or less than equimolar amount of said diamine. The invention of US'577 is directed towards the findings that the composition of the US'577 are stable at 0°C, where as compositions with greater than equimolar amounts of magnesium than diamine show no such stability, and fail after a few days at 0°C..
US 6927200 relates to liquid detergent compositions comprising an amine oxide surfactant, an alkyl alkoxy sulphate surfactant, and preferably magnesium salts. Part of the alkyl alkoxy sulphate surfactant is a branched material, resulting in improved physical stability of the compositions at low temperatures. The inventors of US'200 have found that the use of this branched material addresses the problem of low temperature instability, even in compositions comprising cations, enabling also the formulation of clear products which remain clear at low temperature.

US 2003/0181341 relates to a liquid personal cleansing composition comprising a cleansing surfactant comprising an acyl sarcosinate; and an additional cleansing surfactant selected from the group consisting of an anionic surfactant other than the acyl sarcosinate, an amphoteric surfactant, a zwitterionic surfactant, and water.
US 5998355 provides liquid dishwashing detergent compositions with improved cleaning performance in hard water, comprising from about 1% to about 90% of an anionic surfactant and from about 1% to about 30% of a solvent hydrotrope selected from the group consisting of alkoxylated glycerides, alkoxylated glycerines, esters of alkoxylated glycerines, alkoxylated fatty acids, esters of glycerin, polyglycerol esters and combinations thereof..
US 6174846 provide liquid cleansing compositions in lamellar phase. The invention of US'846 disclose the use of small amounts of hydrophilic emulsifier in combination with a lamellar phase inducing structurant enhances both initial viscosity and free thaw (low temperature) viscosity/stability without sacrificing lather production.
WO 1995/033032 relates to a detergent composition with improved solubility or dissolution of surfactants in aqueous laundering solutions comprising a high level of of surfactant selected from group of alkyl sulfates, alkyl ethoxy sulftaes, secondary alkyl sulfates in combination with oleoyl sarcosinate.
WO 1990/02164 relates to light duty liquid detergents used in hand washing of dishware providing foaming characteristics including magnesium linear dodecyl benzene sulfonate, C9-C13 alkyl mono or polyglucoside, lauric/myristic monoethanolamine, lauric diethanolamine, hydrogen, ethanol and water.
The prior art however does not disclose the achievement of prolonged low temperature stability of the formulations at 0°C. The prior art suggests use of organic diamine, an additional additive, to achieve low temperature stability thereby increasing the formulation cost. Also the maintaining the ratio of magnesium to diamine is critical to attain stability at 0°C.

The prior art also disclose the use of branched alkyl alkoxy sulfate surfactants that leads to poor sudsing performance of formulations. The prior art provides a personal cleansing composition wherein acyl sarcosinate is used to enhance the mildness of the composition and to provide improved skin feel. Different types of hydrotropes are described for cleansing property of the composition along with the usage of other additional reagents such as fatty acids or esters and other polymeric emulsifiers.
The above disclosed prior art teaches increase the solubility of granular laundry detergents in cold water by incorporating oleoyl sarcosinate into the granular laundry detergents. However these do not teach about improving the low temperature stability of liquid dishwashing detergents whose composition is entirely different than the laundry detergents.
Thus, prior art has not entirely addressed the problem of prolonged low temperature stability of hand dishwashing liquid detergent compositions. It mentions the use of certain additional additives to achieve the low temperature stability but such additives are either costly or are likely to degrade the performance of the compositions. Hence, there is still a need of hand dishwashing liquid detergent compositions comprising low cost, easily available, and high performance ingredients and having prolonged low temperature stability.
The formulations of the prior art have certain more drawbacks. Firstly, during the manufacturing process, the viscosity increases tremendously especially at slight alkaline pH, requiring a special type of mixing to get uniformity and to avoid excessive foam generation. Secondly, when stored at low (cold) temperatures, such formulations tend to become non-processable, non-flowable and cloudy or it solidifies. Without intending to be bound by theory, it is believed that since it contains anionic and amphoteric surfactants, when mixed together, forms a bulky water insoluble surfactant complex making a formulation high viscous or sometimes a gel especially at slightly alkaline pH.

To overcome these problems, generally salts of magnesium/calcium like chlorides and sulfates and alcohols and polyols such as propane diols are added as a viscosity modifier and solubilizer. Typical commercial hand dishwashing compositions incorporate divalent ions (Mg. Ca) to ensure adequate grease performance in soft water. Though this additive improves the solubility to some extent, nevertheless does not provides a unique solution to all kind of formulations especially formulations containing fatty alkyl sulfates, amine oxides and nonionics like alkyl polyglycosides. Moreover, the presence of divalent ions lead to slower rates of product mixing with water, poor rinsing and poor low temperature stability properties. Also, preparation of stable dishwashing detergents containing Ca/Mg is very difficult due to the precipitation issues associated with Ca and Mg as pH increases. A perceived problem with alcohols and polyols is that the amount required to achieve formulation stability may be enough to reduce overall levels of viscosity of the composition to an extent that consumers may believe they are not receiving an optimum detergent formulation. High levels of alcohol can also effect the perception of the fragrance used in the composition and affect consumer perception of the product. Alcohols can also contribute to the drying of a user's hands.
Accordingly, it is an aspect of the present invention to provide novel hand dishwashing liquid detergent compositions as well as methods of using these novel compositions. These, and other, aspects, features and advantages will be clear from the following detailed description and the appended claims. All parts, percentages and ratios used herein are expressed as percent weight unless otherwise specified. All documents cited are, in relevant part, incorporated herein by reference.
Therefore, it has been necessary to seek a suitable solution to overcome all aforementioned problems without hampering the crucial attribute of the composition i.e. performance. Surprisingly, the inventors of present invention now found that the use of certain N-long chain acyl neutral amino acids or their salts

facilitates the production of liquid detergent compositions, comprising anionic and amphoteric surfactants, having improved uniformity and prolonged low temperature stability than known or reported before.
OBJECTS OF THE INVENTION
An object of the present invention is to overcome the problems/disadvantages of the prior art.
A further object of the present invention is to provide a hand dishwashing liquid detergent composition with improved uniformity.
Another object of the present invention is to provide a hand dishwashing liquid detergent composition having prolonged low temperature stability and optimum viscosity.
Yet another object of the present invention is to provide a hand dishwashing liquid detergent composition having high performance ingredients.
Yet another object of the present invention is to provide a cost effective and readily available liquid detergent composition.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a hand
dishwashing liquid detergent composition comprising:
(i) an effective amount of N-long chain acyl neutral amino acid or a salt thereof having the formula: R-CO-NR'-CH2 -COOX
wherein, R is a straight or branched chain alkyl or alkenyl residue having from 2 to 18 preferably 8 to18 carbon atoms, R' is hydrogen or methyl radical and X is hydrogen, an alkali metal, the ammonium radical, a

primary, secondary or tertiary amine group or a hydroxylakylamine group;
and (ii) an anionic surfactant other than N- long chain acyl neutral amino acid or
its salt; (iii) an amphoteric surfactant; (iv) 0.1% to 5% by weight of an inorganic salt; (v) optionally, a nonionic surfactant; (vi) optionally, a polyol; and (vii) water
such that the amount the total surfactants, other than N-long chain acyl neutral amino acid or its salt, is at least 10% by weight.
According to another aspect of the present invention there is provided a hand dishwashing liquid detergent composition comprising
(i) 0.5% to 30% by weight of N-acyl sarocosine or N-acyl glycine or their salts.
(ii) atleast 6% by weight of an anionic surfactant other than N-long chain acyl neutral amino acid or its salt;
(iii) atleast 4% to an amphoteric surfactant;
(iv) 0.1 % to 5% by weight of an inorganic salt;
(v) optionally, atleast 0.5% by weight of a nonionic surfactant;
(vi) optionally, atleast 1% by weight of a polyol; and
(vii) water.
According to another aspect of the present invention there is provided a method of producing the hand dishwashing liquid detergent composition of present invention comprising N-acyl sarcosine or N-acyl glycine or their salt consists of:
i. adding N-acyl sarcosine or N-acyl glycine or their salt to the composition comprising an anionic surfactant other than N- long chain acyl neutral amino acid or its salt, an amphoteric surfactant, an inorganic salt,

optionally, a nonionic surfactant, optionally, a polyol and optionally
mixing thoroughly; ii. adding sufficient water; iii. thoroughly agitating the whole mixture; iv. adding citric acid to adjust the pH; and v. thoroughly agitating the whole mixture.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a hand dishwashing liquid detergent composition which exhibits improved uniformity, prolonged low temperature stability and optimum viscosity.
The liquid detergent compositions of present invention are advantageously water soluble over a broad range of temperatures, are easy to formulate and would appear to have no unwanted interaction with most detergent ingredients. More specifically, the liquid detergent compositions of present invention have superior and prolonged low (cold) temperature stability, improved uniformity and optimum viscosity with ease of production.
According to one embodiment of the present invention there is provided a hand
dishwashing liquid detergent composition comprising:
(i) an effective amount of N-long chain acyl neutral amino acid or a salt thereof having the formula: R- CO-NR'-CH2 - COOX
wherein, R is a straight or branched chain alkyl or alkenyl residue having from 2 to 18 preferably 8 to 18 carbon atoms, R' is hydrogen or methyl radical and X is hydrogen, an alkali metal, the ammonium radical, a primary, secondary or tertiary amine group or a hydroxylalkylamine group; and
(ii) an anionic surfactant other than N-long chain acyl neutral amino acid or its salt;

(iii) an amphoteric surfactant;
(iv) 0.1% to 5% by weight of an inorganic salt;
(v) optionally, a nonionic surfactant;
(vi) optionally, a polyol; and
(vii) water
such that amount the total surfactants, other than N-long chain acyl neutral amino
acid or its salt, is at least 10% by weight.
Prolonged low temperature stability herein means a property of hand dishwashing liquid detergent composition by virtue of which it remains homogeneous (clear) for at least 24 hours at 0°C which is never achieved before. This property is achieved in the present invention by incorporating certain N-long chain acyl neutral amino acids or their salts into the liquid detergent compositions comprising anionic and amphoteric surfactants. These N-long chain acyl neutral amino acids or their salts are selected from N-acyl sarcosines, N-acyl glycines, their salts and mixtures thereof. N-acyl sarcosines or N-acyl glycines or their salts into such compositions, facilitates not only the production of uniform composition with great ease but increases the solubility of anionic/amphoteric/nonionic surfactants resulting into a prolonged low (cold) temperature stability. It also increases the mildness of the detergent composition.
The details of the ingredients used herein for the present invention is as follows.
N-long chain acyl neutral amino acid or a salt thereof:
The present invention comprises an "effective amount of N-long chain acyl neutral amino acid or its salt" to achieve the composition of the present invention. By an "effective amount" of N-long chain acyl neutral amino acid or its salt herein is meant an amount which is sufficient to improve, either directionally or significantly at the 90% confidence level, the low temperature stability of the liquid detergent composition against the target temperature, time period and viscosity. Thus, in a composition whose targets include stability for 24 hrs at 0°C

with less than 200 cps viscosity, the formulator will use sufficient N-long chain acyl neutral amino acids or their salts to at least directionally improve the low temperature stability of the composition at 0°C for 24 hrs and having less than 200 cps of viscosity. Importantly, in a fully formulated liquid detergent composition, N-long chain acyl neutral amino acids or their salts can be used at levels which provide at least a directional improvement in stability at low temperatures (i.e. prolonged stability), as will be seen from the examples presented hereinafter. The effective amount of N-long chain acyl neutral amino acid or its salt ranges from 0.5% to 80% by weight preferably from 2% to 30% by weight.
N-long chain acyl neutral amino acids or their salts preferably used herein are selected from N-acyl sarcosines, N-acyl glycines, their salts and mixtures thereof. Examples of the salt include alkali metals (for example, lithium, potassium, sodium, etc.), ammonium, and organic amine (for example, monoethanolamine, diethanolamine, triethanolamine, etc.). N-acyl sarcosines or their salts preferably include, for example, sodium Iauroyl sarcosinate, sodium cocoyl sarcosinate, sodium oleoyl sarcosinate, sodium myristoyl sarcosinate, and mixtures thereof. N-acyl glycines or their salts preferably include, for example, sodium lauroyl glycinate, sodium cocoyl glycinate, sodium oleoyl glycinate, sodium myristoyl glycinate, and mixtures thereof.
Anionic surfactant:
Anionic surfactants, other than N-acyl sarcosines or glycines and their salts, useful in the present invention include, for example, fatty alkyl sulfates, fatty alkyl ether sulfates, alkyl sulfates, ethoxylated alkyl sulfates and mixtures thereof. The preferred anionic surfactants are fatty alkyl sulfates such as sodium cocyl sulfate.
Amphoteric and Zwitterionic surfactant:
Amphoteric and zwitterionic surfactants useful in the present invention include, for example, amine oxides, amphoacetates, betaines and mixtures thereof. The preferred amphoteric surfactants are amine oxides such as lauryl myristyl amine

oxides, cocoamidopropyl amine oxides, lauryl myristyl amidopropyl amine oxides and mixtures thereof.
The amount of total surfactants used in the present invention, other than N-Iong chain acyl neutral amino acids or their salts, is at least 10% by weight. Preferably it is at least 15% by weight.
Inorganic salts:
Inorganic salts useful in the present invention are chosen from the group consisting of alkali metal salts, alkaline metal salts and mixtures thereof. Preferable salts are magnesium salts, calcium salts and sodium salts. Inorganic salts are present in an amount of 0.1% to 5% by weight of total composition. Preferably it is present in amount of 0.2% to 2% by weight of total composition.
Nonionic surfactants:
The present invention may contain nonionic surfactants along with anionic and amphoteric surfactants. Nonionic surfactants useful in the present invention include sucrose polyester surfactants, C10-C18 alkyl polyglycosides, ethoxylates, polyhydroxy fatty acid amide surfactants and mixtures thereof. Among them, preferred nonionic surfactants are alkyl polyglycosides.
Polyol:
The present invention may contain polyols such as diols. The preferred diols are
1,2-propane diol and 1,3-propane diol.
Water:
The balance amount of the composition is water. It is understood that the amount
of water comprising the balance of the detergent composition of the present
invention can be varied depending upon the desired concentration of the final
product.

Other ingredients:
In addition, the liquid detergent compositions of the present invention can contain, if desired, other optional ingredients including any of the usual detersive adjuncts selected from the following: abrasives, bactericides, perfumes, antifungals, insect repellents, hydrotropes, thickeners, processing aids, suds boosters, brighteners, anti-corrosive aids, antioxidants, chelants, dyes, buffers and additives such as water soluble salts of alkaline earth metals such as magnesium sulfate/chloride, and the like, provided that they do not detract from the advantageous properties of the compositions in accordance to the present invention.
The present invention is best illustrated by the following examples.
EXAMPLE I
Example I of Table (a), (b), (c), (d) and (e) are comparative compositions wherein N-acyl sarcosines or N-acyl glycines or their salts are not used. These examples illustrate the stability of liquid detergent compositions which does not comprise N-long chain acyl neutral amino acid or its salt of the present invention. Stability of these compositions at 0°C is evaluated. It can be seen from the data that these compositions are stable for only 3-4 hrs at 0°C and maximum for 10 hrs at 4°C. Also, it was observed that the viscosity of these compositions is in unprocessable range.
EXAMPLES II to IV
Example II of Table (a), (b), (c), (d) and (e) and Example III of Table (a) are compositions within the scope of this invention. These examples illustrate the stability of liquid detergent compositions which comprises N-acyl sarcosine or N-acyl glycine or their salts. In Examples II and III of Table (a), sarcosinate is added in different levels in the same composition of Example I and stability is studied. Stability of all these compositions is evaluated at 0°C except in Example II of Table (e) wherein the composition is evaluated at 4°C. It can be seen from the

data in Table (a), (b), (c), (d) and (e) that these compositions with sarcosinate or glycinate show a drastic enhancement in stability at low temperature as compared to compositions without sarcosinate or glycinate. These compositions are stable for more than 24 hours at 0°C. Also, it can be seen that the viscosity of these compositions after addition of sarcosinate or glycinate is reduced drastically and is in processable range which cannot be achieved without sarcosinate or glycinate of the present invention.
All parts, percentages and ratios used herein are expressed as percent weight unless otherwise specified. In the following examples all levels are quoted as % by weight of the composition.
Table (a)

Ingredient Compositions

I
(comparative) II III
Sodium Cocyl Sulfate 13.0 13.0 13.0
Lauryl myristyl amine oxide 4.0 4.0 4.0
Alkyl polyglycoside 0 0 0
Magnesium chloride 0 0 0
1,2-propane diol 0 0 0
Citric acid 0.2 0.2 0.2
Sodium lauroyl sarcosinate 0 2.0 3.0
Water q.s. to 100%
pH (as such) 7.6 7.3 7.5
Viscosity (cps) 13500 75 20
Stability at 0°C (in hours) 3 50 75

Table (b)

Ingredient Compositions

I
(comparative) II
Sodium Cocyl Sulfate 13 13.0
Lauryl myristyl amine oxide 4 4.0
Alkyl polyglycoside 0.5 0.5
Magnesium chloride 0 0
1,2-propane diol 0 0
Citric acid 0.2 0.2
Sodium lauroyl sarcosinate 0 2.0
Water q.s.to 100%
pH (as such) 7.6 7.5
Viscosity (cps) 16000 150
Stability at 0°C (in hours) 3 24
Table (c)

Compositions
Ingredient I
(comparative) II
Sodium cocyl sulfate 13.0 13.0
Lauryl myristyl amine oxide 4.0 4.0
Alkyl polyglycoside 0.5 0.5
Magnesium chloride 0.2 0.2
1,2-propane diol 1.5 1.5
Citric acid 0.2 0.2
Sodium lauroyl sarcosinate 0 2.0

Water q.s. to 100%
pH (as such) 8.0 7.5
Viscosity (cps) 22000 4000
Stability at 0°C (in hours) 4 35
Table (d)

Ingredient Compositions

I
(comparative) II
Sodium cocyl sulfate 13.0 13.0
Lauryl myristyl amine oxide 4.0 4.0
Alkyl polyglycoside 0.5 0.5
Magnesium chloride 0.2 0.2
1,3-propanediol 1.5 1.5
Citric acid 0.2 0.2
Sodium Cocoyl Glycinate 0 2.0
Water q.s. to 100%
pH (as such) 8 7.65
Viscosity (cps) 22000 5000
Stability at 0°C (in hours) 4 48
Table (e)

Ingredient Compositions

I
(comparative) II
Sodium cocyl sulfate 13.0 13.0
Lauryl myristyl amine oxide 4.0 4.0

Alkyl polyglycoside 0.5 0.5
Magnesium chloride 0.2 0.2
l,3-propane diol 1.5 1.5
Citric acid 0.2 0.2
Sodium Cocoyl Glycinate 0 2.0
Water q.s. to 100%
pH (as such) 7.45 7.1
Viscosity (cps) 250 425
Stability at 4°C (in hours) 10 >70
Method of Preparation:
A preferred method of producing the liquid detergent composition of present invention comprising N-acyl sarcosine or N-acyl glycine or their salt consists of:
a) adding N-acyl sarcosine or N-acyl glycine or their salt to composition of Example I [of Table (a) or (b) or (c) or (d) or (e)] and optionally mixing thoroughly;
b) adding sufficient water;
c) thoroughly agitating the whole mixture;
d) adding citric acid to adjust the pH; and
e) thoroughly agitating the whole mixture.
As an alternative procedure, N-acyl sarcosine or N-acyl glycine or their salt can be added to a premix of the required amounts of compositions of Example I. This is then added to round bottom flask and then mix thoroughly for 30 min at 100 rpm.
The pH of the composition is preferably from about 6 to about 9, more preferably from about 7 to 8. The compositions of the present invention have a viscosity of at least 20 cps.

Test Procedure:
The compositions are tested for their stability at low temperature by the following test method.
1) Prepare the composition as mentioned above and adjust the pH and viscosity.
2) Wait for foam to settle
3) Transfer the composition to 100 ml transparent test bottles

4) Keep the bottles in ice bath where temperature is maintained at 0°C and at 4°C
5) Observe the bottle at 1 hour interval for clarity in both ice baths.
Evaluation of Results:
If the mixture (composition) does not show significant improvement in stability and uniformity when compared to non sarcosinate/glycinate mixture, quantity of sarcosinate/glycinate is increased to achieve the desired stability. When evaluating stability to determine the appropriate use rate of sarcosinate/glycinate, a minimum stability period of 24 hrs is considered the acceptable criterion.
Although the present inventors described specific examples of the present inventive concept, it is considered that the broad aspects of the same not to be limited to the specific substances mentioned therein but to include various other compounds of equivalent function and constitution. It is understood that any suitable changes modifications and variations may be made without departing from the spirit and scope of the invention.

We claim:
1. A hand dishwashing liquid detergent composition comprising
i. an effective amount of N-long chain acyl neutral amino acid or a salt thereof having the formula:
R-CO-NR'-CH2 - COOX wherein, R is a straight or branched chain alkyl or alkenyl residue having from 2 to 18 preferably 8 to 18 carbon atoms, R' is hydrogen or methyl radical and X is hydrogen, an alkali metal, the ammonium radical, a primary, secondary or tertiary amine group or a hydroxylalkylamine group;
ii. an anionic surfactant other than N-long chain acyl neutral amino acid or its salt;
iii. an amphoteric surfactant;
iv. 0.1% to 5% by weight of an inorganic salt;
v. optionally, a nonionic surfactant;
vi. optionally, a polyol; and
vii. water
such that the amount of the total surfactants, other than N-long chain acyl
neutral amino acid or its salt, is at least 10% by weight of composition.
2. The hand dishwashing liquid detergent composition as claimed in claim 1
wherein N-long chain acyl neutral amino acid is N-acyl sarcosine or N-
acyl glycine or their salts and mixtures thereof.
3. The hand dishwashing liquid detergent composition as claimed in claim 2
wherein N-acyl sarcosine or its salt is selected from sodium lauroyl
sarcosinate, sodium cocoyl sarcosinate, sodium oleoyl sarcosinate, sodium
myristoyl sarcosinate, and mixtures thereof.

4. The hand dishwashing liquid detergent composition as claimed in claim 2 wherein N-acyl glycine or its salt is selected from sodium lauroyl glycinate, sodium cocoyl glycinate, sodium oleoyl glycinate, sodium myristoyl glycinate, and mixtures thereof.
5. The hand dishwashing liquid detergent composition as claimed in claim 2, wherein the salts of N-acyl sarcosine or N-acyl glycine is selected from lithium, potassium, sodium, ammonium, and organic amine.
6. The hand dishwashing liquid detergent composition as claimed in claim 5, wherein the organic amine is selected from monoethanolamine, diethanolamine, triethanolamine.
7. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said anionic surfactant is selected from fatty alkyl sulfates, fatty alkyl ether sulfates, alkyl sulfates, ethoxylated alkyl sulfates and mixtures thereof.
8. The hand dishwashing liquid detergent composition as claimed in claim 7, wherein said anionic surfactant is fatty alkyl sulfates preferably sodium cocyl sulfate.
9. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said amphoteric and zwitterionic surfactant is selected from amine oxides, amphoacetates, betaines and mixtures thereof.
10. The hand dishwashing liquid detergent composition as claimed in claim 9, wherein said amphoteric surfactants are amine oxides selected from lauryl myristyl amine oxides, cocoamidopropyl amine oxides, lauryl myristyl amidopropyl amine oxides and their mixtures thereof.

11. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said nonionic surfactant is selected from sucrose polyester surfactants, C10-C18 alkyl polyglycosides, ethoxylates, polyhydroxy fatty acid amide surfactants and their mixtures thereof.
12. The hand dishwashing liquid detergent composition as claimed in 11, wherein said nonionic surfactants are alkyl polyglycosides.
13. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said inorganic salt is selected from alkali metal salts, alkaline metal salts and mixtures thereof,
14. The hand dishwashing liquid detergent composition as claimed in claim 13, wherein said inorganic salt is selected from magnesium salts, calcium salts and sodium salts.
15. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said polyol is selected from 1,2-propane diol and 1,3-propane diol.
16. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said pH of the said composition is 6 to 9, preferably 7 to 8.
17. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said composition is stable at a viscosity less than 200 cps.
18. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said composition has a viscosity of at least 20 cps.
19. The hand dishwashing liquid detergent composition as claimed in claim 1, wherein said composition has prolonged low temperature stability.

20. The hand dishwashing liquid detergent composition as claimed in claim 19, wherein said composition is stable at 0°C for at least 24 hours.
21. A hand dishwashing liquid detergent composition comprising
a. 0.5% to 30% by weight of N-acyl sarocosine or N-acyl glycine or
their salts.
b. atleast 6% by weight of an anionic surfactant other than N-long
chain acyl neutral amino acid or its salt;
c. atleast 4% to an amphoteric surfactant;
d. 0.1% to 5% by weight of an inorganic salt;
e. optionally, atleast 0.5% by weight of a nonionic surfactant;
f. optionally, atleast 1% by weight of a polyol; and
g. water.
22. A method of producing the hand dishwashing liquid detergent composition
of present invention comprising N-acyl sarcosine or N-acyl glycine or
their salts consists of:
i. adding N-acyl sarcosine or N-acyl glycine or their salt to the composition comprising an anionic surfactant other than N- long chain acyl neutral amino acid or its salt, an amphoteric surfactant, an inorganic salt, optionally, a nonionic surfactant, optionally, a polyol and optionally mixing thoroughly;
ii. adding sufficient water;
iii. thoroughly agitating the whole mixture;
iv. adding citric acid to adjust the pH; and
v. thoroughly agitating the whole mixture.