Indian Patents. 208320:PROCESS FOR THE PREPARATION OF IMPROVED NOVOLAC PHENOL-FORMALDEHYDE COMPOSITIONS AND PRODUCTS MADE THEREFROM

Title of Invention	PROCESS FOR THE PREPARATION OF IMPROVED NOVOLAC PHENOL-FORMALDEHYDE COMPOSITIONS AND PRODUCTS MADE THEREFROM
Abstract	A process for the prepertion of novoloc-based phenol-formaldehyde compositions comprising reacting formaldehyde with phenol ion the ratio of 0.50 to 0.95 moles of formaldehyde (37% w/w aqueous solution) to one mole of phenol in the presence of acid catalyst

Full Text	The present invention relates to a process for the preparation of improved Novolac based Phenol-Formaldehyde compositions and products made therefrom. The Novolac phenol-formaldehyde composition prepared according to the present invention has improved strength and integrity which when compounded with certain blowing agents, curing agents, reinforcing agents, cross linking agents, flexibilising agents and chain extenders as described herein, a homo-dispersed system is obtained which when subjected to farther processing with or without rigid or flexible facing substrate at elevated temperatures gradually, results into a very rigid structural cellular composite which can be possibly used as structural element for the low temperature as well as high temperature applications such as automotive, projectiles, heavy duty filed vehicles for military use, construction industry, aviation and space technology, ship building, nuclear technology and radio electronics and can also be used as a heat shield for the engine compartment. Such composites can withstand substantial vibration and stress and strain during use, wherein the integrity of the structural composite is maintained. BACKGROUND OF THE INVENTION Cellular products from phenol-formaldehyde composition have been known for a long time. These compositions are either Resol based on Novolac based and are synthesized from phenols, formaldehydes and an acidic or alkaline catal}-st at an elevated temperature and selectively dehyderated to the required level. The conventional phenol-formaldehyde compositions have certain drawbacks which make it less efficient. The prominent drawbacks of the prior arts are mentioned here: Most of the phenol-formaldehyde resin based composites suffer form: a) loss of mechanical property if sandwched between metal substrate. b) decrease in bonding strength at high temperature 2nd some limes undergo thermal decomposition. c) lack of sufficient elasticity and resistance against abrasion. d) composite conversion when stored at low temperanre (at 15°C to 28° C) in an enclosed container or sealed poly-coated bags. e) insufficient dimensional stability, low compressive strength and relatively high moisture content. Once the bond between the cellular matrix and substrate is lost due to any of the above mentioned weaknesses that conventional phenol-formaldehyde composition possess, the structural part ceases to function as a composite and the integrity of the matrix is lost, resulting in a breach in the thermal barrier. The strength of the composite decreases considerably causing several functional failures. The main objective of the present invention is a to provide an advanced method/process tor the preparation of Novolac-based improved phenol-tbrmaldehyde compositions and products made therefrom, which possess improved properties than their prior arts. The new Novolac-based phenol-formaldehyde compositions, prepared from present advanced process have improved mechanical strength high bonding ability, greater elasticity and abrasion-resistance, higher dimensional stability and very low moisture content. Due to improved properties, these improved phenol-formaldehyde compositions are when compounded with certain blowing agents curing agents, reinforcing agents, cross-lining agents, flexibilising agents and certain expenders result into very rigid structural cellular composite which can be possibly used as structural element for the low temperature as well high temperature applications. The present advanced process of preparing improved Novolac-based phenol-formaldehyde composition explains the use of reactants like mixture of several types of phenols and mixture of several types of aldehyde (all ingredients taken in some fixed proportions) along with the application of a mixture of acidic or alkaline catalysts at slightly elevated temperature (between 50° C to 100°C). Application of such mixture of several phenols and several aldehydes and mixture of catalysts, along with the maintenance of reaction conditions is new. It is a further object of the present invention to provide composites made of improved Novolac phenol-formaldehyde compositions which would overcome the structunii and bond failure of the conventional Novolac-based phenol-formaldehyde composites and would maintain the integrity of the composites in severe stress and strain induced application areas. The details about the invention is substantially written below: Details of the advanced process of the preparation of improved Novolac-based phenol-formaldehyde composition and products made therefrom : The present invention relates to a process for the perpetration of Novolac-based phenol-formaldehyde composition comprising reacting formaldehyde with phenol in the ratio of 0.5 to 0.95 moles of formaldehyde (37% W/W aqueous solution) to one mole of phenol in the presence of acid catalyst as herein described. According to a preferred embodiment of the invention, the molar ratio of Phenol to formaldehyde is 1 :0.897. According to another preferred embodiment of the invention, the reaction product of phenol and formaldehyde obtained is distilled at atmospheric pressure to remove the reaction water. * According to yet another preferred embodiment of the invention, the pH cf the reaction product is adjusted to 7.1. In addition to phenol, other phenolic compounds may be substituted for upto approximately 15% of phenol Examples of other phenolic compounds include resorcinol, catacol, ortho/metal/para-cresols,. xylenols, ethyl phenols, para tertiary butylphenols, nonyl phenol, cashewnut shell oils and the like. Binuclear phenolic compounds may also be used in such preparations. The most preferred composition is obtained with 0.1 of para-tert butyl phenol along with equal proportion of ethyl phenol. In addition to formaldehyde (37% w/w formaldehyde solution) itself, other aldehydes can also be used upto 10% of the formaldehyde. Examples of other suitable aldehydes are benzaldehyde acetaldehyde, chloral, furtural, glyoxal and the like. However the preferred aldehyde is the formaldehyde with a minor quantity of other aldehyde. The most preferred composition would be one containing 0.05 moles of fufural along with 37% w/w formaldehyde solution. The acid catalysts which can be used of the preparation of Novolac phenol formaldehyde composition are hydrochloric acid, siphuric acid, oxalic acid, benzoic acid or their salts or a mixture thereof. A combination of the aforesaid catalysts may be used to obtain synergistic effect without causing any deteriorating effect on the properties of the resin composition obtained. The reaction between phenol and formaldehyde is carried out at temperature between 50°C to 100°C and then allowed to reflux at atmospheric pressure. The preferred temperature of reaction is around 90°C. The carrying out of reaction at lower temperatures other than specified herein would result in the production of phenol formaldehyde alcohols which is not desirable. The time required to prepare the improved Novalac phenol formaldehyde composition would be between 4 to 16 hours depending upon the type of the reactants, proportion of the reactants and the reaction conditions adopted. Preferably the reaction time is maintained between 8 to 12 hours. The reaction product obtained when cooled is a solid hard mass, is brittle and can be broken easily or can be powdered. For removing the reaction water the distillation of the reaction mass is carried out at the atmospheric pressure. However, vacuum distillation is necessary at the end of dehydration period at 700 mmHg pressure. During the distillation the temperature normally increases to 140°C to 160°C and it is made sure that the temperature of poly-condensation does not exceed 4 160°C. The extent of poly-condensation of phenol and formaldehyde for the preparation of improved Novalac composition would depend upon the temperature of reaction, extent of polymerisation sought, concentration of the reacting components the nature and the concentration of the catalyst employed. The most suitable Novalac phenol formaldehyde composition can be prepared by carefully choosing the correct proportion of the reactants, the catalyst and maintaining the correct reaction conditions. The properties of the phenol- formaldehyde composition prepared according to the presence invention can be improved by adding several types of conventional additives such as flexibilizers, fillers, hardening agents, blowing agents, extenders, colourants and the like. In order to induce more elasticity to the said composition (100 pbw), 5-15 pbw of natural rubber, nitrile rubber, chloroprene rubber, styrene-butadine rubber and various rubber latexs can be added. Such compound/s are added during the end of the polymerisation cycle of the phenol formaldehyde composition in the reactor to achieve a homogenous dispersion to flexibilize the composition. Alternatively such compounds can be added during the compounding operation on heated roller mill subsequently. Latax rubber, porofor, hicar and krynac type of modified 0 rubber compounds yield the best results. The process of preparation of the phenol formaldehyde oligommcric compounds for the manufacture of structural composites involves compounding the basic phenol formaldehyde elasticated composition and plasticizer, blowing agent, hardening agent with or without filler. The components are mixed in necessary proportions and subsequently milled several times to obtain physically inseparable homogenous mixture, producing semi cross-linking product which could be softened at temperature between 75° to 85°C to transform the composition to a viscoelastic masticated state. Examples of particulate or fibrous fillers which can be added to the phenol-formaldehyde composition prepared according to the present invention are exfoliated mica, copper dust, aluminium perlite, siesal, wood flour, wood particles, silicates, carbonates or various metals Products manufactured from such filled phenol formaldehyde composition can withstand temperatures upto 250°C without thermal degradation for specific period of time. Examples of blowing agents which can be added to the composition prepared according to this invention are sodium carbonate, magnesium carbonate, potassium carbonate, calcium carbonate and the like which liberate carbon dioxide gas due to chemical reaction with the residual water content of the system or with the accessible free acid in the system. In addition, metal powders such as zinc, iron, aluminium, magnesium and the like have also been used to generate hydrogen gas with various acids for expansion of the matrix depending on the end application of the composite and their physical parameters required. The most effective gas generating system being diisocyanate of nitrourea, oxibisbenzyl-sulphonyl hydrozyl, diazoaminohydrazide, dinitroso pentamethylene tetramine, hydrogen paraoxide, flouracarbon and the like. The phenol-formaldehyde composition prepared exhibit considerable shelf life before composite conversion, when stored between 15°C to 2S^C in an enclosed container or sealed poly-coated bags, in contrary to the prior act materials which need to be stored between 40°C and 10°C beyond which their shelf life deteriorates drastically rendering the materials non-usable. The composition prepared exhibits the bulk density of 0.18 to 0.5 gm/cm3 depending on the formulation and the filler used. The composition exhibits very good dimensional stability of 0.05% to 1.5% between temperatures ranging from 70°C to 220°C. The apparent density normally ranges between 0.18 to 3.5 gm/cm3 depending on grade of the manufacture for specific application. The compressive strength varies between 6 to 35 kg/cm whereas the moisture uptake varies 0,1 to 25 g/m (24 hrs immersion) depending on the grade chosen. Since many apparently different embodiments of the present invention could be made without departing from the spirit and scope thereof, it is intended that the description of the present invention herein be interpi^d as illustrative only and not limiting in any manner whatsoever. We Claim: (1) An advanced process for the preparation of improved Novolac-based phenol-formaldehyde composition comprising reacting mixture of formaldehyde and several other aldehydes (upto 10% of formaldehyde) with mixture of phenol and several penol compounds (upto 15% of phenol) in the ratio of 0.50 to 0.95 mole of formaldehyde-aldehyde mixture (37% w/w aqueous solution) to one mole of phenol-phenolic compounds mixture in presence of a mixture of acid catalysts and hence the most preferred reaction mixture comprises 37% w/w formaldehyde solution containing 0.05 mole furfural, phenol-phenolic compound mixture containing 0.1 mole of para-tert-butylphenol along with equal proportion of ethyl phenol; combination of acid catalysts like hydrochloric acid, sulphuric acid, oxalic acid, benzoic acid and/or their salts; maintaining the molar ratio of phenolic and aldehyde fractions as 1:0.897 at pH 7.1 and reaction temperature 90oC. (2) A process as claimed in claim 1 wherein the molar ratio of phenol to formaldehyde is 1:0.897. (3) A process as claimed in claim 1 and 2 wherein addition to phenol, other phenolic compounds, such as herein are substituted upto 15% of the phenol. (4) A process as claimed in claim 3 wherein as other phenolic compound 0.! mole of para-tert butylapheno! along with equal proportion of ethyl phenol is used. (5) A process as claimed in claim 1 to 4 wherein in addition to formaldehyde itself, other aldehydes, such as herein described, are added upto 10% of the formaldehyde. (6) A process as claimed in claim 1 to 5 wherein 0.05 moles of furfuraldehyde along with 37% w/w formaldehyde solution is used. (7) A process as claimed in claim 1 to 6 wherein the reaction between phenol and formaldehyde is carried out at temperature of between phenol and formaldehyde is carried out at temperature of between 50°C to 100°C and then allowed to reflux at atmospheric pressure. (8) A process as claimed in claims 1 to 7 wherein the reaction between phenol and formaldehyde is carried out for a period from 4 to 16 hours. (9) A process as claimed in claim 8 wherein the reaction between phenol and formaldehyde is carried out for a period from 8 to 12 hours: (10) A process as claimed in claim 1 to 9 wherein the pH of the phenol- formaldehyde composition obtained is adjusted at 7.1.

Full Text

The present invention relates to a process for the preparation of improved Novolac based Phenol-Formaldehyde compositions and products made therefrom.
The Novolac phenol-formaldehyde composition prepared according to the present invention has improved strength and integrity which when compounded with certain blowing agents, curing agents, reinforcing agents, cross linking agents, flexibilising agents and chain extenders as described herein, a homo-dispersed system is obtained which when subjected to farther processing with or without rigid or flexible facing substrate at elevated temperatures gradually, results into a very rigid structural cellular composite which can be possibly used as structural element for the low temperature as well as high temperature applications such as automotive, projectiles, heavy duty filed vehicles for military use, construction industry, aviation and space technology, ship building, nuclear technology and radio electronics and can also be used as a heat shield for the engine compartment. Such composites can withstand substantial vibration and stress and strain during use, wherein the integrity of the structural composite is maintained.
BACKGROUND OF THE INVENTION
Cellular products from phenol-formaldehyde composition have been known for a long time. These compositions are either Resol based on Novolac

based and are synthesized from phenols, formaldehydes and an acidic or alkaline catal}-st at an elevated temperature and selectively dehyderated to the required level.
The conventional phenol-formaldehyde compositions have certain drawbacks which make it less efficient. The prominent drawbacks of the prior arts are mentioned here:
Most of the phenol-formaldehyde resin based composites suffer form:
a) loss of mechanical property if sandwched between metal substrate.
b) decrease in bonding strength at high temperature 2nd some limes undergo thermal decomposition.
c) lack of sufficient elasticity and resistance against abrasion.
d) composite conversion when stored at low temperanre (at 15°C to 28° C) in an enclosed container or sealed poly-coated bags.
e) insufficient dimensional stability, low compressive strength and relatively high moisture content.
Once the bond between the cellular matrix and substrate is lost due to any of the above mentioned weaknesses that conventional phenol-formaldehyde composition possess, the structural part ceases to function as

a composite and the integrity of the matrix is lost, resulting in a breach in the thermal barrier. The strength of the composite decreases considerably causing several functional failures.
The main objective of the present invention is a to provide an advanced method/process tor the preparation of Novolac-based improved phenol-tbrmaldehyde compositions and products made therefrom, which possess improved properties than their prior arts. The new Novolac-based phenol-formaldehyde compositions, prepared from present advanced process have improved mechanical strength high bonding ability, greater elasticity and abrasion-resistance, higher dimensional stability and very low moisture content. Due to improved properties, these improved phenol-formaldehyde compositions are when compounded with certain blowing agents curing agents, reinforcing agents, cross-lining agents, flexibilising agents and certain expenders result into very rigid structural cellular composite which can be possibly used as structural element for the low temperature as well high temperature applications.
The present advanced process of preparing improved Novolac-based phenol-formaldehyde composition explains the use of reactants like mixture of several types of phenols and mixture of several types of aldehyde (all ingredients taken in some fixed proportions) along with the application of a

mixture of acidic or alkaline catalysts at slightly elevated temperature (between 50° C to 100°C).
Application of such mixture of several phenols and several aldehydes and mixture of catalysts, along with the maintenance of reaction conditions is new. It is a further object of the present invention to provide composites made of improved Novolac phenol-formaldehyde compositions which would overcome the structunii and bond failure of the conventional Novolac-based phenol-formaldehyde composites and would maintain the integrity of the composites in severe stress and strain induced application areas. The details about the invention is substantially written below:
Details of the advanced process of the preparation of improved Novolac-based phenol-formaldehyde composition and products made therefrom :
The present invention relates to a process for the perpetration of Novolac-based phenol-formaldehyde composition comprising reacting formaldehyde with phenol in the ratio of 0.5 to 0.95 moles of formaldehyde (37% W/W aqueous solution) to one mole of phenol in the presence of acid catalyst as herein described.
According to a preferred embodiment of the invention, the molar ratio of Phenol to formaldehyde is 1 :0.897.

According to another preferred embodiment of the invention, the reaction product of phenol and formaldehyde obtained is distilled at
atmospheric pressure to remove the reaction water.
*
According to yet another preferred embodiment of the invention, the pH cf the reaction product is adjusted to 7.1.
In addition to phenol, other phenolic compounds may be substituted for upto approximately 15% of phenol Examples of other phenolic compounds include resorcinol, catacol, ortho/metal/para-cresols,. xylenols, ethyl phenols, para tertiary butylphenols, nonyl phenol, cashewnut shell oils and the like. Binuclear phenolic compounds may also be used in such preparations. The most preferred composition is obtained with 0.1 of para-tert butyl phenol along with equal proportion of ethyl phenol.
In addition to formaldehyde (37% w/w formaldehyde solution) itself, other aldehydes can also be used upto 10% of the formaldehyde. Examples of other suitable aldehydes are benzaldehyde acetaldehyde, chloral, furtural, glyoxal and the like. However the preferred aldehyde is the formaldehyde with a minor quantity of other aldehyde. The most preferred composition would be one containing 0.05 moles of fufural along with 37% w/w formaldehyde solution.

The acid catalysts which can be used of the preparation of Novolac phenol formaldehyde composition are hydrochloric acid, siphuric acid, oxalic acid, benzoic acid or their salts or a mixture thereof. A combination of the aforesaid catalysts may be used to obtain synergistic effect without causing any deteriorating effect on the properties of the resin composition obtained.
The reaction between phenol and formaldehyde is carried out at temperature between 50°C to 100°C and then allowed to reflux at atmospheric pressure. The preferred temperature of reaction is around 90°C. The carrying out of reaction at lower temperatures other than specified herein would result in the production of phenol formaldehyde alcohols which is not desirable.
The time required to prepare the improved Novalac phenol formaldehyde composition would be between 4 to 16 hours depending upon the type of the reactants, proportion of the reactants and the reaction conditions adopted. Preferably the reaction time is maintained between 8 to 12 hours. The reaction product obtained when cooled is a solid hard mass, is brittle and can be broken easily or can be powdered.
For removing the reaction water the distillation of the reaction mass is carried out at the atmospheric pressure. However, vacuum distillation is

necessary at the end of dehydration period at 700 mmHg pressure. During the distillation the temperature normally increases to 140°C to 160°C and it is made sure that the temperature of poly-condensation does not exceed
4
160°C.
The extent of poly-condensation of phenol and formaldehyde for the preparation of improved Novalac composition would depend upon the temperature of reaction, extent of polymerisation sought, concentration of the reacting components the nature and the concentration of the catalyst employed. The most suitable Novalac phenol formaldehyde composition can be prepared by carefully choosing the correct proportion of the reactants, the catalyst and maintaining the correct reaction conditions.
The properties of the phenol- formaldehyde composition prepared according to the presence invention can be improved by adding several types of conventional additives such as flexibilizers, fillers, hardening agents, blowing agents, extenders, colourants and the like.
In order to induce more elasticity to the said composition (100 pbw), 5-15 pbw of natural rubber, nitrile rubber, chloroprene rubber, styrene-butadine rubber and various rubber latexs can be added. Such compound/s are added during the end of the polymerisation cycle of the phenol formaldehyde composition in the reactor to achieve a homogenous

dispersion to flexibilize the composition. Alternatively such compounds can be added during the compounding operation on heated roller mill subsequently. Latax rubber, porofor, hicar and krynac type of modified
0
rubber compounds yield the best results.
The process of preparation of the phenol formaldehyde oligommcric
compounds for the manufacture of structural composites involves
compounding the basic phenol formaldehyde elasticated composition and
plasticizer, blowing agent, hardening agent with or without filler. The
components are mixed in necessary proportions and subsequently milled
several times to obtain physically inseparable homogenous mixture,
producing semi cross-linking product which could be softened at
temperature between 75° to 85°C to transform the composition to a
viscoelastic masticated state.
Examples of particulate or fibrous fillers which can be added to the phenol-formaldehyde composition prepared according to the present invention are exfoliated mica, copper dust, aluminium perlite, siesal, wood flour, wood particles, silicates, carbonates or various metals Products manufactured from such filled phenol formaldehyde composition can withstand temperatures upto 250°C without thermal degradation for specific period of time.

Examples of blowing agents which can be added to the composition
prepared according to this invention are sodium carbonate, magnesium
carbonate, potassium carbonate, calcium carbonate and the like which
liberate carbon dioxide gas due to chemical reaction with the residual water
content of the system or with the accessible free acid in the system. In
addition, metal powders such as zinc, iron, aluminium, magnesium and the
like have also been used to generate hydrogen gas with various acids for
expansion of the matrix depending on the end application of the composite
and their physical parameters required. The most effective gas generating
system being diisocyanate of nitrourea, oxibisbenzyl-sulphonyl hydrozyl,
diazoaminohydrazide, dinitroso pentamethylene tetramine, hydrogen
paraoxide, flouracarbon and the like.
The phenol-formaldehyde composition prepared exhibit considerable shelf life before composite conversion, when stored between 15°C to 2S^C in an enclosed container or sealed poly-coated bags, in contrary to the prior act materials which need to be stored between 40°C and 10°C beyond which their shelf life deteriorates drastically rendering the materials non-usable.
The composition prepared exhibits the bulk density of 0.18 to 0.5 gm/cm3 depending on the formulation and the filler used. The composition exhibits very good dimensional stability of 0.05% to 1.5% between

temperatures ranging from 70°C to 220°C. The apparent density normally ranges between 0.18 to 3.5 gm/cm3 depending on grade of the manufacture for specific application. The compressive strength varies between 6 to 35 kg/cm whereas the moisture uptake varies 0,1 to 25 g/m (24 hrs immersion) depending on the grade chosen.
Since many apparently different embodiments of the present invention could be made without departing from the spirit and scope thereof, it is intended that the description of the present invention herein be interpi^d as illustrative only and not limiting in any manner whatsoever.
We Claim:
(1) An advanced process for the preparation of improved Novolac-based
phenol-formaldehyde composition comprising reacting mixture of
formaldehyde and several other aldehydes (upto 10% of
formaldehyde) with mixture of phenol and several penol compounds
(upto 15% of phenol) in the ratio of 0.50 to 0.95 mole of
formaldehyde-aldehyde mixture (37% w/w aqueous solution) to one
mole of phenol-phenolic compounds mixture in presence of a
mixture of acid catalysts and hence the most preferred reaction
mixture comprises 37% w/w formaldehyde solution containing 0.05
mole furfural, phenol-phenolic compound mixture containing 0.1

mole of para-tert-butylphenol along with equal proportion of ethyl phenol; combination of acid catalysts like hydrochloric acid, sulphuric acid, oxalic acid, benzoic acid and/or their salts; maintaining the molar ratio of phenolic and aldehyde fractions as 1:0.897 at pH 7.1 and reaction temperature 90oC.
(2) A process as claimed in claim 1 wherein the molar ratio of phenol to
formaldehyde is 1:0.897.
(3) A process as claimed in claim 1 and 2 wherein addition to phenol,
other phenolic compounds, such as herein are substituted upto 15%
of the phenol.
(4) A process as claimed in claim 3 wherein as other phenolic compound 0.! mole of para-tert butylapheno! along with equal proportion of ethyl phenol is used.
(5) A process as claimed in claim 1 to 4 wherein in addition to formaldehyde itself, other aldehydes, such as herein described, are added upto 10% of the formaldehyde.
(6) A process as claimed in claim 1 to 5 wherein 0.05 moles of furfuraldehyde along with 37% w/w formaldehyde solution is used.

(7) A process as claimed in claim 1 to 6 wherein the reaction between
phenol and formaldehyde is carried out at temperature of between
phenol and formaldehyde is carried out at temperature of between
50°C to 100°C and then allowed to reflux at atmospheric pressure.
(8) A process as claimed in claims 1 to 7 wherein the reaction between
phenol and formaldehyde is carried out for a period from 4 to 16
hours.
(9) A process as claimed in claim 8 wherein the reaction between phenol
and formaldehyde is carried out for a period from 8 to 12 hours:
(10) A process as claimed in claim 1 to 9 wherein the pH of the phenol-
formaldehyde composition obtained is adjusted at 7.1.

Documents:

1209-mas-1999-abstract.pdf

1209-mas-1999-claims duplicate.pdf

1209-mas-1999-claims original.pdf

1209-mas-1999-correspondence others.pdf

1209-mas-1999-correspondence po.pdf

1209-mas-1999-description complete duplicate.pdf

1209-mas-1999-description complete original.pdf

1209-mas-1999-form 1.pdf

1209-mas-1999-form 19.pdf

1209-mas-1999-form 26.pdf

1209-mas-1999-form 3.pdf

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Patent Number

208320

Indian Patent Application Number

1209/MAS/1999

PG Journal Number

26/2007

Publication Date

29-Jun-2007

Grant Date

20-Jul-2007

Date of Filing

21-Dec-1999

Name of Patentee

ROCON INTERNATIONAL

Applicant Address

21-A, ARCHANA ENCLAVE, ENTRENCHMENT ROAD, MARREDPALLY (EAST) SECUNDERABAD - 500026

Inventors:

#	Inventor's Name	Inventor's Address
1	ROY PRANABESH CHANDER	21-A, ARCHANA ENCLAVE, ENTRENCHMENT ROAD, MARREDPALLY (EAST) SECUNDERABAD - 500026

PCT International Classification Number

C08G008/10

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA