FORM 2
THE PATENT ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION
External application
2. APPLICANT (S)
(a) NAME : ELDER PHARMACEUTICALS LTD.
(b) NATIONALITY : INDIAN
(c) ADDRESS : Elder House, Plot No. C/9, Dalia Indl. Estate,
Off. New Link Road, Andheri (W),
Mumbai - 400 058, 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 invention relates to dimethicone composition, use of dimethicone composition for control of ectoparasites and method of use of dimethicone composition for control of ectoparasites.
BACKGROUND OF THE INVENTION
Ectoparasites include sucking lice (Anoplura) and biting lice (Mallophaga), fleas, keds, mites and ticks. Lice are instrumental in spread of at least three diseases viz. epidemic typhus, trench fever and relapsing fever.
An individual faces problem of head lice from the days of childhood. Head lice infest human hair and spread by contact. Head lice infestations are commonly experienced among school going children and also in adult individuals due to spreading by contact of head scalp and hair. There are many diverse reasons that create conditions of hair and the scalp in supporting infestation of head lice. The problem is more felt in case of young children, human individuals who have long hair, or in case of individuals who do not keep their hair and scalp of the head clean. People of all age groups can be victims of lice infestation due to several reasons. The main tiny insect that creates the discomfort is lice. Lice are mobile. A female louse lays few hundred eggs in its life. A female louse is known to be capable of laying fertile eggs within 12 days after hatching. Although lice may be transferred by contact, eggs remain adhered to hair and the infestation spreads in multiple heads. Human lice are spread by crowding and common usage of clothing and combs. It causes severe discomfort to an individual. Besides discomfort, there is itching sensation. Scrubbing by nails or other pointed articles may cause wound which may develop pus and sepsis. Itching head in public places and while in company of friends also looks bad. Lice - ova - lice cycle continues and so continues the scratching and discomfort. A hard chltinous exoskeleton protects head lice and eggs from external elements. Lice may be affected by use of an insecticide but not the eggs. The only way to resolve the

problem is to get rid of the lice and the ova by immobilizing them and physically removing them.
It is necessary to remove the live lice, prevent adhered eggs from hatching and remove the eggs from hair and scalp in order to eradicate the infestation. The prior art has addressed the problem by providing some alternative solutions such as physical removal or anti-lice formulations.
Combing hair with a special comb having very fine gaps between the teeth was used to remove the eggs and mature lice. But such combing is often painful and many a times perceived as shameful act. Moreover, this intensive labour work requires a good discipline for several times a day.
There are several preparations available in the market for killing lice. As the lice are to be killed, some of the compositions use pesticides and insecticides. This is not a good way of resolving the problem. It has several potential disadvantages such as possible penetration of the corrosive chemicals through skin into body fluid and blood circulation. Such crossing of the barrier may give rise to severe and serious systemic problems. Possibility of damage to sensitive organs due to poisonous chemical can not be ruled out. Some of such preparations use some silicones as optional ingredient, main ingredient being pesticide such as Malathion or other organo-phosphorus compound. Some of the insecticides and pesticides have very strong unpleasant odour. In addition to disadvantages associated with these preparations as indicated in preceding text, use of such preparations fails to provide intended result after some time and do not effectively eliminate head lice. Use of Hexachlorocyclohexane, Malathion and Pyrethrins besides causing allergic reactions, cannot prevent re-infestation. Such alternatives instead of solving problems give rise for other more severe and dangerous problems. Problem is further worsened by possibility and ability of lice to develop resistance to insecticide and pesticide compounds.

Some pediculicide preparations cause nerve damage because these preparations use nervous system toxicants which are capable of either inhibiting or over-potentiating synapse-synapse or neuro-muscular junction transmission. Some of these have acetylcholinesterase inhibitor activity. Pesticides mainly chlorinated phenyl and cyclodiene compounds such as DDT, chlordane, heptachlor, dieldrin and aldrin, or the carbamate esters carbaryl, Carbofuran, Aldicarb, and Baygon, or organic thiophosphate esters such as Diazinon, Malathion, Parathion, and Dicapthon and the synthetic Pyrethroid compounds Allethrin, Permethrin, Resmethrin, and Fenvalerate present some serious threat to human health due to their toxicity. Such compounds also cause environmental pollution. Use of DDT, Chlordane, Heptachlor, Dieldrin, and Aldrin is contraindicated.
Some formulations available in the market have a very strong odour that is not so good. Some people are allergic to flavors and odour. These individuals cannot use flavored compositions. The chemicals used in the compositions for control of ectoparasites sometimes have a very strong undesirable odour. To mask that undesirable odour of chemicals, other strong flavors are used. This further complicates the making and use of compositions for control of ectoparasites.
Sometimes the nature of substances poses severe limitations for its use. A highly viscous substance cannot flow easily and its processing becomes difficult. Some substances change their properties at very low or at higher temperatures. Their flow properties also change.
Some formulations available in the market use such chemicals that at times cause lesions, allergy to the skin.
Some of the formulations use chemicals which necessitates their storage under specific conditions.
Therefore although prior art attempted to solve the problem, the means adapted in past to eradicate the infestation have always fallen short of expected results due

to several reasons, limitations and were not satisfactory. Still a desirable solution is not in sight.
WO2001019190 describes compositions for control of arthropods comprising at least one siloxane other than solely a linear alkyl or aryl siloxane having a viscosity less than 20000 centistokes as active ingredient. Composition preferably comprises volatile and non-volatile siloxane, wherein non-volatile siloxane is dimethicone or dimethiconol. Siloxane with viscosity of less than 20000cSt is essential feature of invention.
WO2001078670 and WO2001078671 describe hair coloring compositions wherein silicones are described as additional additives. Similarly WO2002100418 describes compositions which further include additional component dimethicone.
DE202006004172 Ul describes compositions for killing ectoparasites and/or their ova comprising low viscosity linear polysiioxane having a viscosity of less than 10 cSt, a high viscosity linear polysiioxane having a viscosity greater than 90cSt and at least one spreading agent. A low viscosity linear polysiioxane is dimethicone having a viscosity of lcSt and a higher viscosity linear polysiioxane is dimethicone having a viscosity of l00cSt. Higher viscosity is around l00cSt.
US4146619 describes method of controlling ectoparasites or their ova by applying at least one linear siloxane polymer having repeating units of R2SiO where R is alkyl or aryl and having a viscosity of less than about 20000 centistokes and polymer being dimethicone, simethicone or phenyl dimethicone. Viscosity of less than about 20000 centistokes being essential feature of invention.
DE 102008004676 describes a foamable composition comprising one or more linear or branched hydrocarbons and dimethicone as stabilizing agent.

WO2009105617 describes treatment of body insect infestation comprising topically applying a chemical formulation comprising a siloxane and a surfactant to insect infestation and allowing it to remain on insect infestation, where siloxane is dimethicone.
WO2009144712 describes a pediculicidal composition for killing both lice and their eggs comprising a mixture of tea tree oil, geranium oil, neem oil, andiroba oil, rosemary oil, and lemongrass oil, diluted in a solvent composition comprising SD alcohol 40, diethylhexyl adipate, cyelopentasiloxane and dimethicone.
Prior art is devoid of compositions for control of ectoparasites or arthropods wherein siloxane polymer or dimethicone of far higher viscosity is used. Prior art is also devoid of compositions comprising combinations of very high viscosity siloxane polymer or dimethicone, with low viscosity siloxanes polymer or dimethicone as are disclosed by the invention in the present application as described hereafter.
WO2001019190 is silent about compositions comprising siloxane polymer of viscosity above 20000 cSt which is the essential feature of invention in the present application.
DE202006004172U1 do not teach compositions or method of controlling ectoparasites with compositions comprising siloxane polymer having high viscosity of about 60000cSt as disclosed by invention in the present application.
US4146619 also does not teach compositions wherein siloxane polymers of viscosity of about 60000cSt are used. US4146619 does not teach combination compositions wherein two dimethicone moieties are combined.

US6663876 teaches a method of manufacturing a medicament for killing ectoparasites on a subject, comprising, providing a non-aqueous, volatile liquid comprising a cyclic siloxane, and admixing a fatty acid ester at a concentration of between 25% and 65% w/w and in an amount sufficient to kill ectoparasites. The patent claim has fatty acid ester as an essential feature which is absent in the invention in the present application.
Prior art therefore either teaches use of siloxanes, polysiloxanes or dimethicone having either too low viscosity of about 100cSt or higher viscosity of about less than 20000cSt for control of ectoparasites or arthropods. It is silent about ;ompositions comprising siloxane polymers having viscosity of about 60000cSt or the compositions comprising combinations of siloxane polymers having viscosity of about 60000cSt and one with viscosity of about 1 OcSt as disclosed by invention in the present application.
Although the prior art described use of lower viscosity siloxanes in controlling ectoparasites, prior art is silent on use of siloxanes with higher viscosities for controlling ectoparasites. Higher viscosity ingredient in general is difficult to process and difficult to apply. Siloxanes are known to be water repellants and sticky. Probably these properties of high viscosity siloxanes are responsible for their lesser use in applications and lesser use in compositions for controlling ectoparasites.
Infestation of the human body by lice is an increasingly prevalent social and health problem in many countries. Concerns of health and environment, less effectiveness of known alternatives provided by prior art necessitates urgent need for a safe and effective solution for control of ectoparasites lice and ova.

OBJECTIVE OF THE INVENTION
The main object of the invention is to provide a stable composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane polymer has a viscosity of about 40000cSt to about 80000cSt, preferably 600G0cSt and the other has a viscosity of about l0cSt and the use of the composition.
Another object of the invention is to provide a stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane polymer has a viscosity of about 40000cSt to about 80000cSt preferably 60000cSt and the other has a viscosity of about lOcSt and the use of the composition.
Yet another object of the invention is to provide a stable composition for control of ectoparasites comprising combination of dimethicone polymers such that one siloxane polymer has a viscosity of about 40000cSt to about 80000cSt preferably 60000cSt and the other has a viscosity of about lOcSt and the use of the composition.
Yet another object of the invention is to provide an odorless stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about lOcSt and the use of the composition.
Yet another object of the invention is to provide an odorless stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about l0cSt that can be stored at room temperature and the use of the composition.

Yet another object of the invention is to provide a composition comprising combination of polymers of siloxanes wherein both polymers are dimethicones and the use of the composition.
Yet another aspect of the invention is to provide the method of use of compositions comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about l0cSt. for control of ectoparasites.
SUMMARY OF THE INVENTION
Accordingly present invention provides an effective, stable composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about l0cSt and the use of the composition.
In particular the invention provides a stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one polymer is dimethicone having a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other dimethicone has a viscosity of about lOcSt and the use of the composition.
In one embodiment the invention also provides an odorless stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about lOcSt and the use of the composition.

One another embodiment of the present invention also provides an odorless stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about l0cSt that can be stored at room temperature and the use of the composition.
As yet another embodiment, the present invention provides the method of use of compositions comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about lOcSt, for control of ectoparasites.
In particular the invention also provides the method of use of a stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one polymer is dimethicone having a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other dimethicone has a viscosity of about lOcSt
DETAILED DESCRIPTION OF THE INVENTION
This invention relates to the stable composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about lOcSt and the use of the composition.
The invention also relates to the method of use of the stable composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about l0cSt.

In particular the invention relates to a stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one polymer is dimethicone having a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other dimethicone has a viscosity of about l0cSt and the use of the composition.
It was surprisingly found that a composition comprising a combination of polymers of siloxanes wherein one polymer is dimethicone having a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other dimethicone has a viscosity of about lOcSt is effective in control of ectoparasites such as lice and ova.
Thus one aspect of the present invention provides an effective, stable composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one siloxane has a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other has a viscosity of about l0cSt.
In particular the invention provides a stable liquid composition for control of ectoparasites comprising combination of polymers of siloxanes wherein one polymer is dimethicone having a viscosity of about 40000cSt to about 80000cSt, preferably 60000cSt and the other dimethicone has a viscosity of about 1 OcSt.
It was surprisingly found that embodiments of the present invention can be stored at room temperature of about 25°C to about 30°C and yet they retain their property to control ectoparasites insects and their ova,.
Viscosity is expressed as kinematic viscosity, a ratio of viscosity to density and is measured in stokes or centistokes. Where the density of a substance is close to 1, absolute and kinematic viscosity has almost the same numerical values.

In this specification, "controlling" ectoparasites includes repelling, reducing in number and eradicating the live forms e.g. ectoparasites. Control of ova includes killing and reducing the viability of said ova. In this specification use of the compositions in controlling ectoparasites includes single or multiple or repetitive applications for a period ranging from about 10 minutes to about 24 hours. Preferably the invention provides the use of a composition comprising a high viscosity siloxane polymer having a viscosity of about 40000 to about 80000cSt. preferred being about 60000cSt and a low viscosity siloxane polymer having a viscosity of about l0cSt for the control of ectoparasites, insects and their ova. The word about indicates the variation range of about 10%.
People skilled in the art will appreciate that commercially available siloxane polymer products can be obtained in a wide range of viscosity grades and it will further be understood that the appropriate viscosity grade would be selected.
Compositions for use according to the present invention preferably comprise from 5 - 25 % w/w of a high viscosity siloxane polymer, more preferably from 10 - 20 % w/w, and from 75 - 95 % w/w of a low viscosity siloxane polymer, more preferably 80 - 90 % w/w.
Most preferably the high viscosity siloxane polymer comprises 15-17 %w/w and the low viscosity siloxane polymer comprises 83 - 85 %w/w of the composition.
The high viscosity siloxane polymer is preferably a linear siloxane derivative, in particular a dimethicone with 60000cSt.
The typical process of preparation of composition of the invention in the present application is as follows ;
1) Weigh low viscosity polymer and charge to suitable vessel,

2) Add weighed quantity of high viscosity polymer to low viscosity polymer in the vessel,
3) Mix the contents with the help of suitable mixer to form a uniformly mixed blend,
4) Filter the blend through suitable filter,
5) Fill the measured quantity of the filtered blend into suitable container, cap and seal.
The vessels used should be constructed of a material that does not react with the contents. It should not give out any traces into the contents.
Persons skilled in the art would be able to select the appropriate stirrer for uniform mixing.
A suitable filter assembly known to the persons skilled in the art can be used to filter the contents.
Filling of filtered blend into suitable containers can be carried out by conventional manual or automatic means.
All essences and flavors certified by food and drug administration to be safe for use can be incorporated. Non limiting examples of essences and flavors either natural or artificial that can be incorporated in the composition include clove, geranium, lavender, lemon, rosemary, cinnamon, juniper, lemon grass, myrrh, neroli, peppermint, opine, Camomile, rose, sage, sandalwood or mixtures thereof. These are indicative and non limiting examples.
In the present invention room temperature is a range of temperature from 15°C to 30°C.

Terms volatile and non-volatile have same meaning as is commonly understood by persons skilled in the art in chemistry.
One preferred embodiment comprises 100 % w/w of combination of siloxane polymers i.e. dimethicones of two types one with high viscosity and the other with low viscosity.
Composition of the present invention can be formulated into mousse, gel, lotion, spray by the techniques known to the persons skilled in the art. Such formulations preferably comprise at least 80%, more preferably 85% and advantageously at least 90% of the siloxane composition.
Surfactants may be incorporated into the liquid composition of the invention so that it may as well act as a shampoo while at the same time retaining its insecticidal properties. Such compositions perform the two functions one that of cleaning hair and second that of removing any head lice and ova present, thus providing added protection against re-infestation.
The viscosity of the finished composition including any additives or excipients may conveniently be in the range 10 to 300 centistokes, preferably 50 to 200 centistokes and advantageously 80 to 160 centistokes depending upon the type of formulation i.e. whether it is gel or lotion or spray.
For use in treating head lice and/or their ova the composition may be applied to the hair and scalp of a subject infested with head lice. The action of the composition kills or incapacitates the lice, and the ova. For a single treatment the composition is preferably used in an amount of from 5 to 30 ml depending upon hair length and thickness. These dosage levels relate to the composition in undiluted form. If the composition is used in diluted form e.g. as a shampoo, spray or gel the actual volume employed should be increased accordingly to maintain an effective level of the active component(s).

After applying the composition to the head and scalp, the composition preferably remains in contact with the affected area for a period of from 10 minutes to 24 hours. Lice may be destroyed within a period of 10 minutes to 8 hours. A longer period may be required to kill the ova. It is preferred that the composition remains in contact with the ova for a period of 8 - 24 hours. For example composition may be applied in the night and kept as such overnight. A composition may if desired be left on the hair for a longer period without adverse effect on the host subject.
After treatment with composition, the hair may be washed with a suitable shampoo, to remove the dead Jice and ova. The treatment may be repeated to destroy any lice emerging from ova remaining after the first application. Such second application can be made 7 days after the first treatment.
The compositions may also be used for veterinary purposes, for example for the control of parasites on non-human animals. The animal is preferably a mammal or a bird and may include for example, cattle, pigs, sheep, goats, horses, deer, fowl e.g. hens, as well as companion animals, such as dogs and cats.
Thus second aspect of the invention provides a method of use of composition in controlling ectoparasites.
Method
Lice
Assay lice reference / distilled water
Batches of about thirty lice are transferred to the lids of 3 petri dishes of 5.5 cm diameter. Every batch is transferred on a round paper filter, covering the bottom of each petridish. Then directly sprayed and soaked in 300μl of distilled water (lice reference), that diffuses quickly. The test samples are left at room

temperature in the laboratory, without changing the paper filter, during a contact time of 8 hours, corresponding with the treatment (water as reference). The dishes were kept open. At the end of the contact time of 8 hours with water, the lice are washed with a soft shampoo, then rinsed with distilled water before being transferred to a new round paper filter, placed on the bottom of the petridish. After rinsing with distilled water, a series of observations of the state of the lice is made: dead (D), knock down (KD, varying from strong anomalies in displacement, to lethargy, not representing any movement) or alive (A),
The number of lice of each state is counted and documented:
After 1 hour
After 6 hours
After 24 hours.
Assay lice Experimental / composition of the invention.
For the composition of the invention, batches of 36 lice are transferred to the lids of 3 petridishes of 5.5 cm diameter. Every batch is transferred on a round paper filter, covering the bottom of each petridish. Then directly soaked in 300μl of composition of the invention (lice experimental), that diffuses quickly. The test samples are left at room temperature in the laboratory, without changing the paper filter, during a contact time of 8 hours. The dishes are kept open. At the end of the contact time of 8 hours with composition of the invention, the lice ate washed with a soft shampoo, then rinsed with distilled water before being transferred to a new round paper filter, placed on the bottom of the petridish. After rinsing with distilled water, a series of observations of the state of the lice is made : dead (D), knock down (KD varying from strong anomalies in displacement, to lethargy, not representing any movement) or alive (A),
The number of lice of each state is counted and documented: After 1 hour

After 6 hours
After 24 hours.
Results
Lice
Observation after 8 hours of contact, followed by a washing and then a rinsing
Table 1: Results in number and % of lice experimental, Dead, Knock down, and Alive, observed at +lh, +6h and +24h, after 8h of contact, then washing, followed by a rinsing, in comparison with the lice reference in contact with distill water.

Lice : 220

Dead Knock-Down Alive
Time of Test/Number Number % Number % Number %
observation total lice
after 8
hours of
contact,
washing
and then a
rinsing
+lh Reference /
112 7 6,25 0 0 105 93,75

Composition 108 100 0 0 0 0
of the
invention /108
+6h Reference / 112 8 7,15 0 0 104 92,85

Composition 108 100 0 0 0 0
of the
invention
/I08
+24 h Reference / 112 95 84,80 10 8,95 7 6,25

Composition 108 100 0 0 0 0
of the
invention /108

Thus third aspect of the invention provides use of compositions provided by the present invention.
In the fourth aspect the invention provides a composition comprising Dimethicone 60000cSt 16%w/w and Dimethicone l0cSt 84%w/w for control of ectoparasites, as illustrated in Example 2.
Preferred features of all aspects are same and it is combination of high viscosity and low viscosity polymer of siloxane where high viscosity is in the range of about 40000cSt to about 80000cSt, preferably 60000cSt and lower viscosity is in the range of about l0cSt and capability of such composition in control of ectoparasites and ova.
EXAMPLES
Example 1
Dimethicone 60000cSt 16%w/w
Cyclomethicone D4 84%w/w
The process of preparation of composition :
1) Weighed Cyclomethicone D4 and charged to suitable vessel,
2) Added weighed quantity of Dimethicone 60000cSt to Cyclomethicone D4 in the vessel,
3) Mixed the contents with the help of suitable mixer to form a uniformly mixed blend,
4) Filtered the blend through suitable filter,
5) Filled the measured quantity of the filtered blend into suitable container, cap and sealed.

Example 2
Dimethicone 60000cSt 16%w/w
Dimethicone 1 0cSt 84%w/w
The process of preparation of composition :
1) Weighed Dimethicone l0cSt and charged to suitable vessel,
2) Added weighed quantity of Dimethicone 60000cSt to Dimethicone lOcSt in the vessel,
3) Mixed the contents with the help of suitable mixer to form a uniformly mixed blend,
4) Filtered the blend through suitable filter,
5) Filled the measured quantity of the filtered blend into suitable container, cap and sealed,
Example 3
Batches of about thirty lice are transferred to the lids of 3 petri dishes of 5.5 cm diameter. Every batch is transferred on a round paper filter, covering the bottom of each petridish. Then directly sprayed and soaked in 300μl of distilled water (lice reference), that diffuses quickly. The test samples are left at room temperature in the laboratory, without changing the paper filter, during a contact time of 8 hours, corresponding with the treatment (water as reference). The dishes were kept open. At the end of the contact time of 8 hours with water, the lice are washed with a soft shampoo, then rinsed with distilled water before being transferred to a new round paper filter, placed on the bottom of the petridish. After rinsing with distilled water, a series of observations of the state of the lice is made : dead (D), knock down (KD, varying from strong anomalies in displacement, to lethargy, not representing any movement) or alive (A),
The number of lice of each state is counted and documented:

After 1 hour
After 6 hours
After 24 hours.
Assay lice Experimental / composition of the invention from Example 2.
For the composition of the invention, batches of 36 lice are transferred to the lids of 3 petri dishes of 5.5 cm diameter. Every batch is transferred on a round paper filter, covering the bottom of each petridish. Then directly soaked in 300μl of composition of the invention (lice experimental), that diffuses quickly. The test samples are left at room temperature in the laboratory, without changing the paper filter, during a contact time of 8 hours, indicated by the promoter. The dishes are kept open. At the end of the contact time of 8 hours with composition of the invention, the lice are washed with a soft shampoo, then rinsed with distilled water before being transferred to a new round paper filter, placed on the bottom of the petridish. After rinsing with distilled water, a series of observations of the state of the lice is made : dead (D), knock down (KD, varying from strong anomalies in displacement, to lethargy, not representing any movement) or alive (A),
The number of lice of each state is counted and documented:
After I hour
After 6 hours
After 24 hours.
Results
Lice
Observation after 8 hours of contact, followed by a washing and then a rinsing.
Table 2: Results in number and % of lice experimental, Dead, Knock down, and Alive, observed at +lh, +6h and +24h, after 8h of contact, then washing,

followed by a rinsing, in comparison with the lice reference in contact with distill water.

Lice : 220

Dead Knock-Down Alive
Time of Test/Number Number % Number % Number %
observation total lice
after 8
hours of
contact,
washing
and then a
rinsing .
+lh Reference / 112 7 6,25 0 0 105 93,75

Composition 108 100 0 0 0 0
of the invention
/108
+6h Reference / 112 8 7,15 0 0 104 92,85

Composition 108 100 0 0 0 0
of the invention
/108
+24 h Reference / 112 95 84,80 102/3+ 8,95 7 6,25

Composition 108 100 0 0 0 0
i of the invention
nos

CLAIMS
We claim,
1. Composition comprising a combination of polymers of siloxanes, wherein one polymer is dimethicone having a high viscosity of about 40000cSt to about 80000cSt and the other is dimethicone having a low viscosity of about l0cSt.
2. Composition according to claim 1, wherein %w/w of a high viscosity siloxane polymer is 5 - 25 %w/w, preferably from 10-20 %w/w, more preferably from 15-17 %w/w, and %w/w of low viscosity siloxane polymer is 75 - 95 %w/w, preferably 80 - 90 %w/w, more preferably 83 -85 %w/w.
3. Composition according to claim 1, wherein the high viscosity siloxane polymer is dimethicone having a viscosity of about 60000 cSt.
4. Process to prepare composition for control of ectoparasites and/or their ova comprising the steps of a) weighing low viscosity polymer and charge to suitable vessel; b) adding weighed quantity of high viscosity polymer to low viscosity polymer in the vessel; c) mixing the contents with the help of suitable mixer to form a uniformly mixed blend; d) filtering the blend through suitable filter; and e) filling the measured quantity of the filtered blend into suitable container, cap and seal
5. A method of controlling of ectoparasites and/or their ova comprising applying the composition as claimed in claim 1 to 2 to the area infested by ectoparasites and /or their ova.