Title of Invention	"A PROCESS FOR THE PREPARATION OF AN IMPROVED BATH USEFUL FOR PROVIDING CORROSION RESISANT PHOSPHATE COATING ON METAL SURFACE AT HIGH TEMPERATURE."
Abstract	A process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature A process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature by preparing 30-40% v/v aqueous solution of. phosphoric acid, adding heavy metal oxides such as ZnO, CaO, MgO, in the range of 20-25% w/v to the above aqueous solution under stirring till dissolution, adding oxidising agents selected from Nitric acid, H2O2, sodium nitrates in the range of 10-15% w/v, adding calcium carbonate, nickel carbonate, copper nitrate, cobalt nitrate to the above mixture, in the range of 0.2 to 0.4% w/v, adding special oxidising agent such as sodium nitrite (NaNO2) in small quantity to the above mixture intermitervtiy in the range of 10-20% w/v. filtering the solution so prepared to get clean solution and diluting the solution with water by around fifty times its volume and heating the bath to a temperature in the range of 50 to 98°C by water.

Title of Invention

"A PROCESS FOR THE PREPARATION OF AN IMPROVED BATH USEFUL FOR PROVIDING CORROSION RESISANT PHOSPHATE COATING ON METAL SURFACE AT HIGH TEMPERATURE."

Abstract

A process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature A process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature by preparing 30-40% v/v aqueous solution of. phosphoric acid, adding heavy metal oxides such as ZnO, CaO, MgO, in the range of 20-25% w/v to the above aqueous solution under stirring till dissolution, adding oxidising agents selected from Nitric acid, H2O2, sodium nitrates in the range of 10-15% w/v, adding calcium carbonate, nickel carbonate, copper nitrate, cobalt nitrate to the above mixture, in the range of 0.2 to 0.4% w/v, adding special oxidising agent such as sodium nitrite (NaNO2) in small quantity to the above mixture intermitervtiy in the range of 10-20% w/v. filtering the solution so prepared to get clean solution and diluting the solution with water by around fifty times its volume and heating the bath to a temperature in the range of 50 to 98°C by water.

Full Text	This invention relates to a process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature. The invention relates basically to the paint and wire industries and also short-term protection of ferrous items especially in prevention of corrosion of structural items, small components etc. Corrosion of metal is bound to take place which could be minimised to a very low level but cannot be checked completely. In order to mitigate the corrosion, different preventive measures namely metallic, inorganic, diffusion, organic coatings, etc. are in use. Out of these preventive measures, phosphate coating is considered to be ideal in many respects and used widely because of its versatility. It is extensively used as a base for paints and lubricants in wire drawing industries. In order to meet the need of the industries different phosphate formulations are available in the market. Hitherto known process uses Zinc Oxide which is costly chemical and sodium fluoride which is pollution prone substance. Other ingredients used are accelerators and activators. The known process consists of reacting Zinc Oxide with phosphoric and Nitric Acids. Other additives are accelerators and activators, such as Nitrates, Nitrites, Chlorats of Cu, Ni and the like and peroxide of Na, Hydrogenf and the like. It is generally observed that the known process takes longer time duration, 10 to 15 minutes at a temperature of 80 to 100° C to get desired coating weight and uses sodium fluoride, a pollution prone ingredient. It is based on two pack system and effective at less dilution (40 times dilution). It is comparatively costly as two pack handling and more concentrated bath increase cost. In the two pack conventional bath, sodium nitrite (oxidising agent) is added frequently to the bath to oxidise ferrous to ferric ions and for activation of sluggish bath. In view of the above facts, it is envisaged to develop a process for the production of Phosphate coating on metal surface by means o£ acid phosphate solutions for the purpose of producing improved resistance to corrosion, improved paint holding properties at a less time and decreased cost of production. The main object of the present invention is to provide a process for the preparation of an improved bath for phosphate coating on mild steel surface at higher temperature which obviates the above mentioned drawbacks. Another object is to develop an improved process for providing corrosion resistant phosphate coatings on metal surface. In the present invention, the solution for phosphate coating is produced by reacting ZnO and CaC03 with phosphoric acid and Nitric Acid. This is followed by incorporation of oxidizing agents and positive actions. Finally, another oxidising agent in the form of Nitrite is added to phosphating bath to regulate and accelerate phosphate coating formation. The value of the free acid and total acid are maintained at 1.5 and 15 points with respect to N/10 NaOH respectively to get desired phosphate coating. The selection of oxidising agents such as nitric acid, sodium nitrite, and the presence of heavy metal ions such as nickel and copper accelerates the reaction. The heavy metal ions and oxidising agents speed up the coating formation by increasing the active nucleation sites and depolarising the cathodic areas by removing hydrogen and this also increases the anodic reaction. Preparation of an aqueons solution consists of. 1.2% by v/v ortho-phosphoric acid and 0.25% v/v Nitric Acid, 0.4% wt/v Zinc Oxide and 0.1% wt/v calcium carbonate. The porosity in the phosphated steels are the channels through which corrosive agents like oxygen and water get access to the base metal. Surface pores on phosphate coatings are singularly responsible for the deterioration of protective property of coatings. The incorporation of Ca ions with Zn ions reduces the porosity and moisture permeability of the phosphate coatings on surfaces of steel. Another novelty of the present invention is that it is a single pack system giving desired coating within minutes. Accordingly the present invention provides a process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature which comprises : i) preparing 30-40% v/v aqueous solution of. phosphoric acid ii) adding heavy metal oxides such as ZnO, CaO, MgO, in the range of 20-25% w/v to the above aqueous solution under stirring till dissolution, iii) adding oxidising agents selected from Nitric acid, H2O2, sodium nitrates in the range of 10-15% w/v, iv) adding calcium carbonate, nickel carbonate, copper nitrate, cobalt nitrate to the above mixture, in the range of 0.2 to 0.4% w/v, v) adding special oxidising agent such as sodium nitrite (NaNO2) in small quantity to the above mixture intermitervtly in the range of 10-20% w/v. vi) filtering the solution so prepared to get clean solution, vii) diluting the solution with water by around fifty times its volume and heating the bath to a temperature in the range of 50 to 98°C by water. In an embodiment of the present invention the total acid may be maintained in the range of 20 to 30 with respect to N/10 NaOH. In another embodiment the free acid maintained may be in the range of 1.0 to 3.0 with respect to N/10 HaOH. In yet another embodiment the temperature of the bath may be maintained at a temperature in the range of 70 to 80°C. Accordingly, the present invention provides an improved process for providing corrosion resistant phosphate coatings on metal surfaces using the above valid bath which comprises: i) dipping the material to be rendered corrosion resistant in the bath prepared as herein described for a period in the range of 1 to 10 minutes. i. .1) removing the phosphated samp IBB out of the bath and w a s h .1 n g w :.i. 11 i w a t e r . According to a feature of the invent .i on metal oxide selected may be of commercial grade with iron content lest;, than O , b"i . The free acid and total acid pointage in t. lie diluted bath (nay be maintained in the range:? of 2 „ O to 3.8 ml and 10 to 30 ml respectively. By the process of present invention phosphate coating on metal surface at higher temperature is done at a less time with improved properties as given in the Table 1. TABLE ••- i KNOWN PROCESS PRESENT INVENTION 1. Dilution 25 ml (conct.) ;: 4O Dilution 20 ml (conc.)% 50 - 1000 ml =LOOO ml 2. pH - 2 to 3 when diluted pH - 2 to 3 when diluted 3. Coating wt -- 14 gm/ at Coating wt — 23 gm/m at 60-70oC in .10 /dins 60--70oC in J.O mins. 4,. Coarse grained coating Fined grainied coating. 5. No sludge formation Slight, sludge formation The following examples are given by way of illustration and should not be construed to limit the scope of the present invention: EXAMPLE - 1 4 Kgs. of Zinc Oxide and 1 Kg . of Calcium Carbonate is reacted with 9 litres of phosphoric (Sp.gravity 1.74) acid and 2 litres of nitric acid (Sp.gravity 1.40) at room temperature. There is generation of heat on adding acids to ZnO/CaCO3 . Addition is made slowly while stirring. 60 gms of nickel carbonate and 10 gms of copper nitrate are then added in the above .mixture while stirring. Finally, 3 Kg.of sodium nitrite is added slowly. The total volume of these resultant solution is made up to 20 litres by water. A mild steel of size one sq.dm. was dipped in the prepared solution diluted to 50 times and heated to 70 - 80° C for one minute removed and washed with water. 2 Results: The phosphate coating on the mild steel was 550 mg/ft at one minute immersion in the solution. EXAMPLE - 2 5 kg. of zinc oxide is treated with 8 litres of phosphoric (sp.gravity 1.71) and 2.5 litres of nitric acid (sp.gravity 1.40) at room temperature. Heat is generated on adding zinc oxide to the acid mixture. Addition is, therefore, done very slowly. 50 gms of nickel carbonate and 8 gms of copper sulphate are then added in the above solution. Finally, 3 kg.of sodium nitrite is added slowly. The total volume of this resultant solution is made upto 20 litres by water. A mild steel of size one sq.dm was dipped in the prepared « ' solution diluted to 50 times and heated to 70 - 80° C for 10 minutes dipping, removed and washed with water. RESULT: 2 Phosphate coating on mild steel obtained is 2140 gms/ft2 at 10 minutes immersion in the solution (diluted to 50 times) at 80 - 90° C. EXAMPLE - 3 5 Kg. of zinc oxide is treated with 9 litres of phophoric acid (sp.gravity 1.71) and 1.5 litres of nitric acid (sp.gravity 1.40) at room temperature. Heat is generated on adding zinc oxide to the acid mixture. Addition is, therefore, done slowly and while stirring. 60 gms of nickel nitrate and 10 gm of copper nitrate are then added in the above solution. Finally, 2 kg. of sodium nit rile is added in the above solution. The total volume of this resultant solution is made upto 20 litres. A mild steel of size one sq. dm. was dipped in the prepared solution diluted to 50 times and heated to 70 - 80°C for 5 minutes dipping removed and washed with water. RESULTS; The phosphate coating obtained on mild steel is 1000 gm/ft2 at 5 minutes immersion in the solution (diluted to 50 times) at 70- 80 °C The following are the main advantage of the present invention: 1. The process of present invention, a single pack phosphating solution is made whereas in the known process two pack solution is required, resulting in the difficulty in handling as well as needing more space. 2. In the process of present invention, the cost is reduced to 25% in comparison to the existing process by using cheaper chemicals. 3. In the present invention, the concentrate is diluted to 50 times whereas in the known process the concentrate is diluted to 40 times (maximum). This results in further reduction in cost. 4. In the present invention, addition of Fluoride accelerator is eliminated. The present invention makes the solution environment friendly whereas known process uses pollution causing fluorides etc. 5. Phosphate coating obtained by this invent ion is more corrosion resistant than the coating obtained by the conventional process. We claim : 1. A process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature which comprises : i) preparing 30-40% v/v aqueous solution of. phosphoric acid ii) adding heavy metal oxides such as ZnO, CaO, MgO, in the range of 20-25% w/v to the above aqueous solution under stirring till dissolution, iii) adding oxidising agents selected from Nitric acid, H2O2, sodium nitrates in the range of 10-15% w/v, iv) adding calcium carbonate, nickel carbonate, copper nitrate, cobalt nitrate to the above mixture, in the range of 0.2 to 0.4% w/v, v) adding special oxidising agent such as sodium nitrite (NaNO2) in small quantity to the above mixture intermitervtly in the range of 10- 20% w/v, vi) filtering the solution so prepared to get clean solution, vii) diluting the solution with water by around fifty times its volume and heating the bath to a temperature in the range of 50 to 98°C by water. 2. A process as claimed in claim 1 wherein the total acid is maintained in the range of 20 to 30 with respect to N/10 NaOH. 3. A process as claimed in claims 1 & 2 wherein the free acid maintained is in the range of 1.0 to 3.0 with respect of N/10 NaOH. . 4. A process as claimed in claims I to 3 wherein the temperature of the bath is maintained at a temperature in the range of 70 to 80°C, 5. A process for providing corrosion resistant phosphate coatings on metal surfaces using the process as claimed in clause 1 to 4 which comprises : i) dipping the materials to be rendered corrosion resistant in the bath prepared as herein described for a period in the range of 1 to 10 minutes. ii) removing the phosphated samples out of the bath and washing with water. 6. A process for the preparation of an improved bath corrosion resistant phosphate coatings on metal surfaces at high temperature substantially as herein described with reference to the examples.

Full Text

This invention relates to a process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature.
The invention relates basically to the paint and wire industries and also short-term protection of ferrous items especially in prevention of corrosion of structural items, small components etc.
Corrosion of metal is bound to take place which could be minimised to a very low level but cannot be checked completely. In order to mitigate the corrosion, different preventive measures namely metallic, inorganic, diffusion, organic coatings, etc. are in use. Out of these preventive measures, phosphate coating is considered to be ideal in many respects and used widely because of its versatility. It is extensively used as a base for paints and lubricants in wire drawing industries.
In order to meet the need of the industries different phosphate formulations are available in the market. Hitherto known process uses Zinc Oxide which is costly chemical and sodium fluoride which is pollution prone substance. Other ingredients used are accelerators and activators.
The known process consists of reacting Zinc Oxide with phosphoric and Nitric Acids. Other additives are accelerators and activators, such as Nitrates, Nitrites, Chlorats of Cu, Ni and the like and peroxide of Na, Hydrogenf and the like.

It is generally observed that the known process takes longer time duration, 10 to 15 minutes at a temperature of 80 to 100° C to get desired coating weight and uses sodium fluoride, a pollution prone ingredient. It is based on two pack system and effective at less dilution (40 times dilution). It is comparatively costly as two pack handling and more concentrated bath increase cost. In the two pack conventional bath, sodium nitrite (oxidising agent) is added frequently to the bath to oxidise ferrous to ferric ions and for activation of sluggish bath.
In view of the above facts, it is envisaged to develop a process for the production of Phosphate coating on metal surface by means o£ acid phosphate solutions for the purpose of producing improved resistance to corrosion, improved paint holding properties at a less time and decreased cost of production.
The main object of the present invention is to provide a process for the preparation of an improved bath for phosphate coating on mild steel surface at higher temperature which obviates the above mentioned drawbacks. Another object is to develop an improved process for providing corrosion resistant phosphate coatings on metal surface.
In the present invention, the solution for phosphate coating is produced by reacting ZnO and CaC03 with phosphoric acid and Nitric Acid. This is followed by incorporation of oxidizing agents and positive actions. Finally, another oxidising agent in the form of Nitrite is added to phosphating bath to regulate and accelerate phosphate coating formation. The value of the free

acid and total acid are maintained at 1.5 and 15 points with respect to N/10 NaOH respectively to get desired phosphate coating. The selection of oxidising agents such as nitric acid, sodium nitrite, and the presence of heavy metal ions such as nickel and copper accelerates the reaction. The heavy metal ions and oxidising agents speed up the coating formation by increasing the active nucleation sites and depolarising the cathodic areas by removing hydrogen and this also increases the anodic reaction. Preparation of an aqueons solution consists of. 1.2% by v/v ortho-phosphoric acid and 0.25% v/v Nitric Acid, 0.4% wt/v Zinc Oxide and 0.1% wt/v calcium carbonate.
The porosity in the phosphated steels are the channels through which corrosive agents like oxygen and water get access to the base metal. Surface pores on phosphate coatings are singularly responsible for the deterioration of protective property of coatings. The incorporation of Ca ions with Zn ions reduces the porosity and moisture permeability of the phosphate coatings on surfaces of steel.
Another novelty of the present invention is that it is a single pack system giving desired coating within minutes.
Accordingly the present invention provides a process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature which comprises :
i) preparing 30-40% v/v aqueous solution of. phosphoric acid ii) adding heavy metal oxides such as ZnO, CaO, MgO, in the range of 20-25% w/v to the above aqueous solution under stirring till dissolution,

iii) adding oxidising agents selected from Nitric acid, H2O2, sodium
nitrates in the range of 10-15% w/v, iv) adding calcium carbonate, nickel carbonate, copper nitrate, cobalt
nitrate to the above mixture, in the range of 0.2 to 0.4% w/v, v) adding special oxidising agent such as sodium nitrite (NaNO2) in small quantity to the above mixture intermitervtly in the range of 10-20% w/v.
vi) filtering the solution so prepared to get clean solution, vii) diluting the solution with water by around fifty times its volume and
heating the bath to a temperature in the range of 50 to 98°C by water. In an embodiment of the present invention the total acid may be maintained in the range of 20 to 30 with respect to N/10 NaOH.
In another embodiment the free acid maintained may be in the range of 1.0 to 3.0 with respect to N/10 HaOH.
In yet another embodiment the temperature of the bath may be maintained at a temperature in the range of 70 to 80°C.
Accordingly, the present invention provides an improved process for providing corrosion resistant phosphate coatings on metal surfaces using the above valid bath which comprises:
i) dipping the material to be rendered corrosion resistant in the bath prepared as herein described for a period in the range of 1 to 10 minutes.

i. .1) removing the phosphated samp IBB out of the bath and
w a s h .1 n g w :.i. 11 i w a t e r .
According to a feature of the invent .i on metal oxide selected may
be of commercial grade with iron content lest;, than O , b"i . The free
acid and total acid pointage in t. lie diluted bath (nay be
maintained in the range:? of 2 „ O to 3.8 ml and 10 to 30 ml
respectively.
By the process of present invention phosphate coating on metal surface at higher temperature is done at a less time with improved properties as given in the Table 1.
TABLE ••- i
KNOWN PROCESS PRESENT INVENTION
1. Dilution 25 ml (conct.) ;: 4O Dilution 20 ml (conc.)% 50
- 1000 ml =LOOO ml
2. pH - 2 to 3 when diluted pH - 2 to 3 when diluted
3. Coating wt -- 14 gm/ at Coating wt — 23 gm/m at
60-70oC in .10 /dins 60--70oC in J.O mins.
4,. Coarse grained coating Fined grainied coating.
5. No sludge formation Slight, sludge formation
The following examples are given by way of illustration and
should not be construed to limit the scope of the present
invention:

EXAMPLE - 1
4 Kgs. of Zinc Oxide and 1 Kg . of Calcium Carbonate is reacted
with 9 litres of phosphoric (Sp.gravity 1.74) acid and 2 litres
of nitric acid (Sp.gravity 1.40) at room temperature. There is
generation of heat on adding acids to ZnO/CaCO3 . Addition is
made slowly while stirring. 60 gms of nickel carbonate and 10 gms
of copper nitrate are then added in the above .mixture while
stirring. Finally, 3 Kg.of sodium nitrite is added slowly. The
total volume of these resultant solution is made up to 20 litres
by water.
A mild steel of size one sq.dm. was dipped in the prepared solution diluted to 50 times and heated to 70 - 80° C for one
minute removed and washed with water.
2
Results: The phosphate coating on the mild steel was 550 mg/ft
at one minute immersion in the solution.
EXAMPLE - 2
5 kg. of zinc oxide is treated with 8 litres of phosphoric
(sp.gravity 1.71) and 2.5 litres of nitric acid (sp.gravity 1.40)
at room temperature. Heat is generated on adding zinc oxide to
the acid mixture. Addition is, therefore, done very slowly. 50
gms of nickel carbonate and 8 gms of copper sulphate are then
added in the above solution. Finally, 3 kg.of sodium nitrite is
added slowly. The total volume of this resultant solution is made
upto 20 litres by water.

A mild steel of size one sq.dm was dipped in the prepared
« '
solution diluted to 50 times and heated to 70 - 80° C for 10 minutes dipping, removed and washed with water.
RESULT:
2 Phosphate coating on mild steel obtained is 2140 gms/ft2 at 10
minutes immersion in the solution (diluted to 50 times) at 80 -
90° C.
EXAMPLE - 3
5 Kg. of zinc oxide is treated with 9 litres of phophoric acid (sp.gravity 1.71) and 1.5 litres of nitric acid (sp.gravity 1.40) at room temperature. Heat is generated on adding zinc oxide to the acid mixture. Addition is, therefore, done slowly and while stirring. 60 gms of nickel nitrate and 10 gm of copper nitrate are then added in the above solution. Finally, 2 kg. of sodium nit rile is added in the above solution. The total volume of this resultant solution is made upto 20 litres.
A mild steel of size one sq. dm. was dipped in the prepared solution diluted to 50 times and heated to 70 - 80°C for 5 minutes dipping removed and washed with water.
RESULTS;
The phosphate coating obtained on mild steel is 1000 gm/ft2 at 5
minutes immersion in the solution (diluted to 50 times) at 70-
80 °C
The following are the main advantage of the present invention:
1. The process of present invention, a single pack phosphating solution is
made whereas in the known process two pack solution is required,
resulting in the difficulty in handling as well as needing more space.
2. In the process of present invention, the cost is reduced to 25% in
comparison to the existing process by using cheaper chemicals.
3. In the present invention, the concentrate is diluted to 50 times whereas in
the known process the concentrate is diluted to 40 times (maximum). This
results in further reduction in cost.
4. In the present invention, addition of Fluoride accelerator is eliminated. The
present invention makes the solution environment friendly whereas known
process uses pollution causing fluorides etc.
5. Phosphate coating obtained by this invent ion is more corrosion resistant
than the coating obtained by the conventional process.

We claim :
1. A process for the preparation of an improved bath useful for providing corrosion resistant phosphate coating on metal surface at high temperature which comprises :
i) preparing 30-40% v/v aqueous solution of. phosphoric acid
ii) adding heavy metal oxides such as ZnO, CaO, MgO, in the range of
20-25% w/v to the above aqueous solution under stirring till dissolution, iii) adding oxidising agents selected from Nitric acid, H2O2, sodium
nitrates in the range of 10-15% w/v, iv) adding calcium carbonate, nickel carbonate, copper nitrate, cobalt
nitrate to the above mixture, in the range of 0.2 to 0.4% w/v, v) adding special oxidising agent such as sodium nitrite (NaNO2) in
small quantity to the above mixture intermitervtly in the range of 10-
20% w/v,
vi) filtering the solution so prepared to get clean solution, vii) diluting the solution with water by around fifty times its volume and
heating the bath to a temperature in the range of 50 to 98°C by water.
2. A process as claimed in claim 1 wherein the total acid is maintained in the
range of 20 to 30 with respect to N/10 NaOH.
3. A process as claimed in claims 1 & 2 wherein the free acid maintained is
in the range of 1.0 to 3.0 with respect of N/10 NaOH. .

4. A process as claimed in claims I to 3 wherein the temperature of the bath
is maintained at a temperature in the range of 70 to 80°C,
5. A process for providing corrosion resistant phosphate coatings on metal
surfaces using the process as claimed in clause 1 to 4 which comprises :
i) dipping the materials to be rendered corrosion resistant in the bath
prepared as herein described for a period in the range of 1 to 10 minutes.
ii) removing the phosphated samples out of the bath and washing with water.
6. A process for the preparation of an improved bath corrosion resistant
phosphate coatings on metal surfaces at high temperature substantially as herein
described with reference to the examples.

Documents:

3352-del-1997-abstract.pdf

3352-del-1997-claims.pdf

3352-del-1997-correspondence-others.pdf

3352-del-1997-correspondence-po.pdf

3352-del-1997-description (complete).pdf

3352-del-1997-form-1.pdf

3352-del-1997-form-19.pdf

3352-del-1997-form-2.pdf

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Patent Number

214800

Indian Patent Application Number

3352/DEL/1997

PG Journal Number

09/2008

Publication Date

29-Feb-2008

Grant Date

15-Feb-2008

Date of Filing

21-Nov-1997

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG, NEW DELHI 110001, INDIA

Inventors:

#	Inventor's Name	Inventor's Address
1	TRIPURARI LAL SHARMA	NATIONAL METALLURGICAL LABORATORY, JAMSHEDPUR BIHAR, INDIA
2	INDER SINGH	NATIONAL METALLURGICAL LABORATORY, JAMSHEDPUR BIHAR, INDIA

PCT International Classification Number

C23C 22/07

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA