Title of Invention	"A PROCESS FOR PREPARATION OF AN IMPROVED AMMONIUM PERCHIORATE BASED GAS GENERATING COMPOSITION"
Abstract	This invention relates to a process for the preparation of an improved gas-generating composition. According to the process a mixture of epoxy binder, energetic plasticizer and a ballistic modifier is prepared in a planetary mixer. An oxidiser is added and mixed followed by mixing under vacuum. A hardener is added therein and is mixed to form a slurry. The slurry is casted in the mould and cured to obtain gas generating composition.

Title of Invention

"A PROCESS FOR PREPARATION OF AN IMPROVED AMMONIUM PERCHIORATE BASED GAS GENERATING COMPOSITION"

Abstract

This invention relates to a process for the preparation of an improved gas-generating composition. According to the process a mixture of epoxy binder, energetic plasticizer and a ballistic modifier is prepared in a planetary mixer. An oxidiser is added and mixed followed by mixing under vacuum. A hardener is added therein and is mixed to form a slurry. The slurry is casted in the mould and cured to obtain gas generating composition.

Full Text	FIELD OF INVENTION The present invention relates to a process for preparation of an improved gas-generating composition having superior burn rates and low flame temperatures. PRIOR ART During recent years, gas generators have gained tremendous importance in view of their wide applications as source of power for a relatively short duration. Gas generators are used for several applications such as driving of turbines of auxilliary power devices, air bag systems, etc which demand clean burning with pollution free exhaust products. The ballistic requirements of these gas generators are low flame temperature (Tf) in the range of 750-2200°C and sustained combustion in the pressure zone of 2-7MPa. The gas-generating compositons used for these applications are generally based on Ammonium nitrate(AN) or Triamino guanidine nitrate (TAGN) as oxidiser. Gas generator devices also find wide applications for augmenting the range of gun projectile by overcoming base drag. Such devices are referred to as base bleed units (BBU) . These units are required to undergo sustained combustion under atmospheric/subatmospheric conditions and have flame temperature (Tf) in the range of 1300 to 3000°C with burn rates of l-5mm/s at atmospheric pressure. The gas-generating compositions used for these applications are generally based on Ammonium Perchlorate (AP) as oxidiser in addition to binder and plasticiser. Ammonium nitrate based gas-generating composition has the disadvantage that due to thermal cycling during storage and exposure in the field, the grains of ammonium nitrate undergo crystal phase transition at 32°C leading to volume changes which are undesirable as these cause dimensional changes of propellant in temperature range of practical importance as well as cause development of cracks Ammonium perchlorate based gas generating compositions known in the art for base bleed units (BBU) use various binders such as cellulose acetate, polyesters, polyethers, hydroxy/carboxy terminated polybutadienes (HTPB/CTPB). Out of these binders, HTPB is preferred in view of its clean cross-linking reaction with isocyanate curative and superior low temperature strain capability. The disadvantage of the above gas generating compositions using ammonium perchlorate and HTPB is that these have low burn rates and combustion inefficiency in actual operating conditions in base bleed units(BBU), particularly under sub-atmospheric conditions. 4 I Another type of ammonium perchlorate based gas generating compositions known in the art, which are recently recommended for BBU, use azido-polymers like glycidyl azide polymer (GAP) as energetic binder/plasticiser which result in improvement of combustion efficiency due to exothermic cleavage of azide bonds near deflagrating surface. The above type of gas generating compositions incorporating azide polymers like GAP as binder have inferior mechanical properties as azide polymers like GAP have relatively higher glass transition temperature (-40°C) and lower load bearing capability as compared to HTPB which result in poor structural integrity of propellant grains. Still another type of ammonium perchlorate based gas generating composition known in the art, use HTPB as binder and GAP which has a low molecular weight, as a plasticiser', The above type of gas generating compositions have the drawback that GAP interacts with isocyanates used as curative for curing of HTPB, resulting in brittle structure. Another disadvantage of the above gas generating composition is gassification due to fast reaction of low molecular weight GAP with the curatives. Further disadvantage of the above type of gas generating compositions is that the different rates of reaction of low molecular weight GAP and high molecular weight HTPB with isocyanate result in inferior mechanical properties. NEED FOR INVENTION Thus, there is a need for ammonium perchlorate based gas generating composition which uses such a binder that GAP does not interfere with the curing process of the binder so as to lead to a gas generating composition without physical defects like voids and cracks. OBJECTS OF THE PRESENT INVENITON The primary object of the present invention is to provide a process for the preparation of an improved gas-generating composition with super burn rate. Another object of the present invention is to provide a process for the preparation of an improved gas-generating composition which is relatively more combustion efficient. Still another object of the present invention is to propose a process for preparation of an improved gas generating composition which incorporates an epoxy polymer as binder which eliminates interference of GAP with curing process of the binder. Yet another object of the present invention is to provide a process for the preparation of an improved gas generating composition which incorporates a ballistic modifier which enables preparation of composition with super burn rates. Additional object of the present invention is to provide a process for preparation of gas generating composition with wide range of burning rates by varying GAP content. Further object of the present invention is to provide a process for preparation of an improved gas generating composition which is slurry castable. Still further object of the present invention is to provide a process for the preparation of an improved gas generating composition which overcomes the problems of gassification experienced in known processes due to fast interaction of low molecular weight glacidyl azide polymer (GAP) with curatives (isocyanates) used for HTPB. Yet further object of the present invention is to provide a procesa which provides a gas generating composition free from physical defect (void/crack). Other objects, features and advantages of the present invention will become apparent from the description and working example that follow. STATEMENT OF INVENITION The present invention proposes slurry-cast technique for ammonium perchlorate based gas-generating compositions with a superior burn rate which can be adopted for base bleed units and allied applications. The composition uses ammonium perchlorate(AP) of 4 micron particle size as the oxidiser, low molecular weight glycidyl azide polymer(GAP) as a plasticiser with an epoxy binder. Fine AP is used to realise high burn rates whereas incorporation of GAP as plasticiser improves the combusion efficiency. Epoxy binder overcomes the problems experienced in the known process which arise due to the use of combination of low molecular weight GAP and high molecular weight hydroxy terminated poly butadiene(HTPB) GAP content is varied to realize wide range of burn rates. A ballistic modifier which is the ferrocene derivative is incorporated in the composition which enables preparation of composition with super burn rates. The composition obtained undergoed sustained combustion even at the chamber pressure of IMPa. The formulation gives burn rate of the order of 34-55mm/s in the pressure range of 1-6.9MPa and has a flame temperature less than 2200°C. DESCRIPTION OF PROCESS OF PRESENT INVENTION According to the present invention, there is provided a slurry-cast technique for preparation of an improved gas generating composition which comprises of the following steps: in the known process which arise due to the use of combination of low molecular weight GAP and high molecular weight hydroxy terminated poly butadiene (HTPB) GAP content is varied to realize wide range of burn rates. A ballistic modifier which is the ferrocene derivative is incorporated in the composition which enables preparation of composition with super burn rates. The composition obtained undergoes sustained combustion even at the chamber pressure of IMPa. The formulation gives burn rates of the order of 34-55 mm/s in the pressure range of l-6.9MPa and has a flame temperature less than 2200° C. The invention will now be illustrated with a working example which is intended to be a typical example to illustrate the working of the present invention and is not intended to be taken restrictively to imply any limitation on the scope of the present invention. WORKING EXAMPLE 60g of novolac epoxy resin, 300g of glycidyl azide polymer and 20g of ferrocene derivative were mixed in a planetary mixer and deaerated by constant agitation for 1 hour. 600g of ammonium perchlorate in fine perticle of 4 microns were then added and mixing continued for 30 minutes without vacuum and for 1 hour under vacuum of 10mm of Hg. 40g of polyamide were added and mixing continued for 20 minutes keeping temperature of about 25° C. The slurry obtained was cast in the mould under vacuum. After casting was over, vacuum was released and mould was transferred to a water jacketed oven for curing at 40°C for 5 days. The burn rates of cured gas generator femulations were determined in the pressure range of l-6.9MPa by employing Acoustic Emission (AE) technique. The formulation prepared as per above example containing 60% AP, 10% epoxy binder, 30% GAP and 2 parts of ballistic modifier exhibited burn rates varying from 34 to 56 mm/s in the pressure range of 1-6.9MPa as per table below:- TABLE -1 (Table Removed) By varying the content of plasticiser like glycidyl azide polymer(GAP) the process of the present invention provides compositions with wide range of burning rates. The burn rates evaluated for different compositions with varying amounts of GAP are tabulated in the following table:- TABLE-II Burn Rates for compositions with different amounts of GAP (Table Removed) Notes AP=Ammonium Perchlorate GAP=Glycidyl Azide Ploymer The calorimetric value and flame temperature of different compositions obtained by varying amounts of GAP are tabulated in Table-III. TABLE-III Calorimetric Value and Flame Temperature of Compositions with different amount of GAP (Table Removed) Notes AP= Ammonium Perchlorate GAP= Glycidyl Azide Polymer As is evident from Table-II and Table-III, the composition with 60% AP, 10% Epoxy binder, 30% GAP and 2 parts/100 of Ferrocene derivative has significantly superior burn rates and low flame temperature. The composition as prepared by the working example has burning rates between 33 to 56mm/s at 1 to 1.69 MPa and flame temperature of 2100°C. The compositions prepared by this invention give stable combustion at as low pressure as 1 MPa. It is to be understood that the process of the present invention is susceptible to modifications, changes and adaptations by those skilled in the art. Such variations, modifications, adaptations are intended to be within the spirit and scope of the present invention which is set forth by the following claims:- WE CLAIM 1. A process for the preparation of an improved gas-generating composition comprising of:~ a) preparing a mixture of epoxy binder, energetic plasticizer and a ballistic modifier in a planetary mixer; to adding an oxidiser and mixing followed tay mixing under vacuum; c) adding a hardener and further mixing to form a slurry; d) casting the slurry in mould and curing. 2. A process for the preparation of an improved gas-generating composition as claimed in claim 1 wherein the said epoxy binder is present in an amount preferably 10 to 407. of the weight of the mixture. 3. A process for the preparation of an improved gas-generating composition as claimed in claim 1 wherein the said plasticiser used is an aside polymer like glycidyl azide polymer (GAP). 4. A process for the preparation of an improved gas-generating composition as claimed in claim 3 wherein said plasticiser is present preferably in an amount of 1O to 307. by weight of mixture. 5. A process for the preparation of an improved gas-generating composition as claimed in claim 1 wherein oxidiser ammonium perechiorate CAP) is used in the preferred oxidiser to binder ratio of 60:40. fc. A process for the preparation of an improved gas-generating composition as claimed in claim 1 wherein the said hardner is polyamide. 7. A process for the preparation of an improved gas-generating composition as claimed in claim 1 wherein the said ballistic modifier used is a ferrocene derivative. 8. A process for the preparation of an improved gas-generating composition as claimed in claim 7 wherein the ballistic modifier is preferably present in an amount of 2 parts per 100 parts of the weight of mixture. 9. A process for the preparation of an improved gas-generating composition as claimed in claim 1 wherein the slurry casting of the composition is ceirried out in a mould kept under vacuum. 10. A process for preparing an improved gas- generating composition substantially as herein described and .illustrated in the example. 11. An improved gas generating composition cornpr i si ng a mi x ture of epoxy binder, energetic plasticizer and a ballistic modifier an oxidizer and a hardener. 12. An improved gas generating composition as claimed in claim 11 wherein the said epoxy binder is present in an amount preferably 10 to 40% of the weight of the mixture. 13. An improved gas generating composition as claimed in claim 11 wherein the said plasticiser used is an azide polymer like glycidyl azide polymer (GAP), 14. An improved gas generating composition as claimed in claim 13 wherein said plasticiser is present preferably in an amount of 10 to 307, by weight of mixture. 15. An improved gas generating composition as claimed in claim 11 wherein oxidiser ammonium perechlorate (AP) is used in the preferred oxidiser to binder ratio of 60:40. 16 „ An improved gas generating composition as claimed in claim 11 wherein the said hardner is polyamide. 17. An improved gas generating composition as claimed in claim 11 wherein the said ballistic modifier used is a ferrocene derivative. 18. An improved gas generating composition as claimed in claim 11 wherein the ballistic modifier is preferably in an amount of 2 parts per 100 parts of the weight of mixture. 19. An improved gas generating composition as claimed in claim 11 wherein the slurry casting of the composition is carried out in a mould kept under vacuum. 20. An improved gas generating composition substantially as herein described and exemplified i n t he e x amp 1 e .

Full Text

FIELD OF INVENTION
The present invention relates to a process for preparation of an improved gas-generating composition having superior burn rates and low flame temperatures.
PRIOR ART
During recent years, gas generators have gained tremendous importance in view of their wide applications as source of power for a relatively short duration. Gas generators are used for several applications such as driving of turbines of auxilliary power devices, air bag systems, etc which demand clean burning with pollution free exhaust products. The ballistic requirements of these gas generators are low flame temperature (Tf) in the range of 750-2200°C and sustained combustion in the pressure zone of 2-7MPa. The gas-generating compositons used for these applications are generally based on Ammonium nitrate(AN) or Triamino guanidine nitrate (TAGN) as oxidiser.
Gas generator devices also find wide applications for augmenting the range of gun projectile by overcoming base drag. Such devices are referred to as base bleed units (BBU) . These units are required to undergo sustained combustion under atmospheric/subatmospheric conditions and have flame temperature (Tf) in the range of 1300 to 3000°C with burn rates of l-5mm/s at atmospheric pressure. The gas-generating compositions used for these applications are generally based on Ammonium Perchlorate (AP) as oxidiser in addition to binder and plasticiser.
Ammonium nitrate based gas-generating composition has the disadvantage that due to thermal cycling during storage and exposure in the field, the grains of ammonium nitrate undergo crystal phase transition at 32°C leading to volume changes which are undesirable as these cause dimensional changes of propellant in temperature range of practical importance as well as cause development of cracks
Ammonium perchlorate based gas generating compositions known in the art for base bleed units (BBU) use various binders such as cellulose acetate, polyesters, polyethers, hydroxy/carboxy terminated polybutadienes (HTPB/CTPB). Out of these binders, HTPB is preferred in view of its clean cross-linking reaction with isocyanate curative and superior low temperature strain capability.
The disadvantage of the above gas generating compositions using ammonium perchlorate and HTPB is that these have low burn rates and combustion inefficiency in actual operating conditions in base bleed units(BBU), particularly under sub-atmospheric conditions.
4 I
Another type of ammonium perchlorate based gas generating compositions known in the art, which are recently recommended for BBU, use azido-polymers like glycidyl azide polymer (GAP) as energetic binder/plasticiser which result in improvement of combustion efficiency due to exothermic cleavage of azide bonds near deflagrating surface.
The above type of gas generating compositions incorporating azide polymers like GAP as binder have inferior mechanical properties as azide polymers like GAP have relatively higher glass transition temperature (-40°C) and lower load bearing capability as compared to HTPB which result in poor structural integrity of propellant grains.
Still another type of ammonium perchlorate based gas generating composition known in the art, use HTPB as binder and GAP which has a low molecular weight, as a plasticiser',
The above type of gas generating compositions have the drawback that GAP interacts with isocyanates used as curative for curing of HTPB, resulting in brittle structure.
Another disadvantage of the above gas generating composition is gassification due to fast reaction of low molecular weight GAP with the curatives.
Further disadvantage of the above type of gas generating compositions is that the different rates of reaction of low molecular weight GAP and high molecular weight HTPB with isocyanate result in inferior mechanical properties.
NEED FOR INVENTION
Thus, there is a need for ammonium perchlorate based gas generating composition which uses such a binder that GAP does not interfere with the curing process of the binder so as to lead to a gas generating composition without physical defects like voids and cracks.
OBJECTS OF THE PRESENT INVENITON
The primary object of the present invention is to provide a process for the preparation of an improved gas-generating composition with super burn rate.
Another object of the present invention is to provide a process for the preparation of an improved gas-generating composition which is relatively more combustion efficient.
Still another object of the present invention is to propose a process for preparation of an improved gas generating composition which incorporates an epoxy polymer as binder which eliminates interference of GAP with curing process of the binder.
Yet another object of the present invention is to provide a process for the preparation of an improved gas generating composition which incorporates a ballistic modifier which enables preparation of composition with super burn rates.
Additional object of the present invention is to provide a process for preparation of gas generating composition with wide range of burning rates by varying GAP content.
Further object of the present invention is to provide a process for preparation of an improved gas generating composition which is slurry castable.
Still further object of the present invention is to provide a process for the preparation of an improved gas generating composition which overcomes the problems of gassification experienced in known processes due to fast interaction of low molecular weight glacidyl azide polymer (GAP) with curatives (isocyanates) used for HTPB.
Yet further object of the present invention is to provide a procesa which provides a gas generating composition free from physical defect (void/crack).
Other objects, features and advantages of the present invention will become apparent from the description and working example that follow.
STATEMENT OF INVENITION
The present invention proposes slurry-cast technique for ammonium perchlorate based gas-generating compositions with a superior burn rate which can be adopted for base bleed units and allied applications. The composition uses ammonium perchlorate(AP) of 4 micron particle size as the oxidiser, low molecular weight glycidyl azide polymer(GAP) as a plasticiser with an epoxy binder. Fine AP is used to realise high burn rates whereas incorporation of GAP as plasticiser improves the combusion efficiency. Epoxy binder overcomes the problems experienced in the known process which arise due to the use of combination of low molecular weight GAP and high molecular weight hydroxy terminated poly butadiene(HTPB) GAP content is varied to realize wide range of burn rates. A ballistic modifier which is the ferrocene derivative is incorporated in the composition which enables preparation of composition with super burn rates. The composition obtained undergoed sustained combustion even at the chamber pressure of IMPa. The formulation gives burn rate of the order of 34-55mm/s in the pressure range of 1-6.9MPa and has a flame temperature less than 2200°C.
DESCRIPTION OF PROCESS OF PRESENT INVENTION
According to the present invention, there is provided a slurry-cast technique for preparation of an improved gas generating composition which comprises of the following steps:
in the known process which arise due to the use of combination of low molecular weight GAP and high molecular weight hydroxy terminated poly butadiene (HTPB) GAP content is varied to realize wide range of burn rates. A ballistic modifier which is the ferrocene derivative is incorporated in the composition which enables preparation of composition with super burn rates. The composition obtained undergoes sustained combustion even at the chamber pressure of IMPa. The formulation gives burn rates of the order of 34-55 mm/s in the pressure range of l-6.9MPa and has a flame temperature less than 2200° C.
The invention will now be illustrated with a working example which is intended to be a typical example to illustrate the working of the present invention and is not intended to be taken restrictively to imply any limitation on the scope of the present invention.
WORKING EXAMPLE
60g of novolac epoxy resin, 300g of glycidyl azide polymer and 20g of ferrocene derivative were mixed in a planetary mixer and deaerated by constant agitation for 1 hour. 600g of ammonium perchlorate in fine perticle of 4 microns were then added and mixing continued for 30 minutes without vacuum and for 1 hour under vacuum of 10mm of Hg. 40g of polyamide were added and mixing continued for 20 minutes keeping temperature of about 25° C. The slurry
obtained was cast in the mould under vacuum. After casting was over, vacuum was released and mould was transferred to a water jacketed oven for curing at 40°C for 5 days.
The burn rates of cured gas generator femulations were determined in the pressure range of l-6.9MPa by employing Acoustic Emission (AE) technique. The formulation prepared as per above example containing 60% AP, 10% epoxy binder, 30% GAP and 2 parts of ballistic modifier exhibited burn rates varying from 34 to 56 mm/s in the pressure range of 1-6.9MPa as per table below:-
TABLE -1
(Table Removed)
By varying the content of plasticiser like glycidyl azide polymer(GAP) the process of the present invention provides compositions with wide range of burning rates. The burn rates evaluated for different compositions with varying amounts of GAP are tabulated in the following table:-

TABLE-II
Burn Rates for compositions with different amounts of GAP
(Table Removed)
Notes AP=Ammonium Perchlorate GAP=Glycidyl Azide Ploymer
The calorimetric value and flame temperature of different compositions obtained by varying amounts of GAP are tabulated in Table-III.
TABLE-III
Calorimetric Value and Flame Temperature of Compositions with different amount of GAP
(Table Removed)
Notes AP= Ammonium Perchlorate GAP= Glycidyl Azide Polymer

As is evident from Table-II and Table-III, the composition with 60% AP, 10% Epoxy binder, 30% GAP and 2 parts/100 of Ferrocene derivative has significantly superior burn rates and low flame temperature. The composition as prepared by the working example has burning rates between 33 to 56mm/s at 1 to 1.69 MPa and flame temperature of 2100°C. The compositions prepared by this invention give stable combustion at as low pressure as 1 MPa.
It is to be understood that the process of the present invention is susceptible to modifications, changes and adaptations by those skilled in the art. Such variations, modifications, adaptations are intended to be within the spirit and scope of the present invention which is set forth by the following claims:-

WE CLAIM
1. A process for the preparation of an
improved gas-generating composition comprising of:~
a) preparing a mixture of epoxy binder,
energetic plasticizer and a ballistic modifier in a planetary mixer;
to adding an oxidiser and mixing followed
tay mixing under vacuum;
c) adding a hardener and further mixing
to form a slurry;
d) casting the slurry in mould and curing.
2. A process for the preparation of an
improved gas-generating composition as claimed in
claim 1 wherein the said epoxy binder is present
in an amount preferably 10 to 407. of the weight
of the mixture.
3. A process for the preparation of an improved
gas-generating composition as claimed in claim 1
wherein the said plasticiser used is an aside polymer like glycidyl azide polymer (GAP).
4. A process for the preparation of an improved
gas-generating composition as claimed in claim 3
wherein said plasticiser is present preferably
in an amount of 1O to 307. by weight of mixture.
5. A process for the preparation of an
improved gas-generating composition as claimed in
claim 1 wherein oxidiser ammonium perechiorate
CAP) is used in the preferred oxidiser to binder
ratio of 60:40.
fc. A process for the preparation of an
improved gas-generating composition as claimed in claim 1 wherein the said hardner is polyamide.
7. A process for the preparation of an
improved gas-generating composition as claimed in
claim 1 wherein the said ballistic modifier used is a ferrocene derivative.
8. A process for the preparation of an
improved gas-generating composition as claimed in
claim 7 wherein the ballistic modifier is
preferably present in an amount of 2 parts per
100 parts of the weight of mixture.
9. A process for the preparation of an
improved gas-generating composition as claimed in
claim 1 wherein the slurry casting of the
composition is ceirried out in a mould kept under
vacuum.
10. A process for preparing an improved gas-
generating composition substantially as herein
described and .illustrated in the example.
11. An improved gas generating composition
cornpr i si ng a mi x ture of epoxy binder, energetic
plasticizer and a ballistic modifier an oxidizer
and a hardener.
12. An improved gas generating composition as
claimed in claim 11 wherein the said epoxy binder
is present in an amount preferably 10 to 40% of
the weight of the mixture.
13. An improved gas generating composition as
claimed in claim 11 wherein the said plasticiser
used is an azide polymer like glycidyl azide
polymer (GAP),
14. An improved gas generating composition as
claimed in claim 13 wherein said plasticiser is
present preferably in an amount of 10 to 307, by
weight of mixture.
15. An improved gas generating composition as
claimed in claim 11 wherein oxidiser ammonium
perechlorate (AP) is used in the preferred
oxidiser to binder ratio of 60:40.
16 „ An improved gas generating composition as claimed in claim 11 wherein the said hardner is polyamide.
17. An improved gas generating composition as claimed in claim 11 wherein the said ballistic modifier used is a ferrocene derivative.
18. An improved gas generating composition as
claimed in claim 11 wherein the ballistic
modifier is preferably in an amount of 2 parts per
100 parts of the weight of mixture.
19. An improved gas generating composition as
claimed in claim 11 wherein the slurry casting of
the composition is carried out in a mould kept
under vacuum.
20. An improved gas generating composition
substantially as herein described and exemplified
i n t he e x amp 1 e .

Documents:

83-del-1999-abstract.pdf

83-del-1999-claims.pdf

83-del-1999-correspondence-others.pdf

83-del-1999-correspondence-po.pdf

83-del-1999-description (complete).pdf

83-del-1999-form-1.pdf

83-del-1999-form-19.pdf

83-del-1999-form-2.pdf

83-del-1999-form-3.pdf

83-del-1999-gpa.pdf

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Patent Number

226585

Indian Patent Application Number

83/DEL/1999

PG Journal Number

01/2009

Publication Date

02-Jan-2009

Grant Date

19-Dec-2008

Date of Filing

14-Jan-1999

Name of Patentee

THE CHIEF CONTROLLER, RESEARCH & DEVELOPMENT

Applicant Address

MINISTRY OF DEFENCE, B-341, SENA BHAWAN, DHQ P.O., GOVERNMENT OF INDIA, NEW DELHI, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	ARUN NARAYAN NAZARE	INDIAN NATIONAL & SUBJECTS OF THE REPUBLIC OF INDIA, HEMRL, PUNE.
2	SHRI NANDAN ASTHANA	INDIAN NATIONAL & SUBJECTS OF THE REPUBLIC OF INDIA, HEMRL, PUNE.
3	VISHWAS GOVIND GHORPADE	INDIAN NATIONAL & SUBJECTS OF THE REPUBLIC OF INDIA, HEMRL, PUNE.
4	SUREKHA SANJAY PATWARDHAN	INDIAN NATIONAL & SUBJECTS OF THE REPUBLIC OF INDIA, HEMRL, PUNE.
5	HARIDWAR SINGH	INDIAN NATIONAL & SUBJECTS OF THE REPUBLIC OF INDIA, HEMRL, PUNE.

PCT International Classification Number

C06B 31/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA