Title of Invention	A PROCESS FOR THE PREPARATION OF A COMPOSITION USEFUL FOR MAKING A PERMANENT MARK ON A SUBSTRATE
Abstract	A process for the preparation of composition useful for making a permanent mark on a substrate which comprises; reacting 5- 30% by wt. of silver nitrate with 0.2-2% by wt. of dye capable of reducing silver nitrate and selected from brilliant green, safranin, methylene blue, para rosaniline, catechol violet, janus green or their mixture, adding 0-0.05% by wt. of sensitising agent such as herein described, adding 70-95% by wt. of solvent consisting of a mixture of water and organic solvents such as herein described in a ratio of 1:9 to 1:1 by volume to obtain the said composition.

Title of Invention

A PROCESS FOR THE PREPARATION OF A COMPOSITION USEFUL FOR MAKING A PERMANENT MARK ON A SUBSTRATE

Abstract

A process for the preparation of composition useful for making a permanent mark on a substrate which comprises; reacting 5- 30% by wt. of silver nitrate with 0.2-2% by wt. of dye capable of reducing silver nitrate and selected from brilliant green, safranin, methylene blue, para rosaniline, catechol violet, janus green or their mixture, adding 0-0.05% by wt. of sensitising agent such as herein described, adding 70-95% by wt. of solvent consisting of a mixture of water and organic solvents such as herein described in a ratio of 1:9 to 1:1 by volume to obtain the said composition.

Full Text	This invention relates to a process for the preparation of composition useful for making a permanent mark on a substrate. The mark applied using the composition of the present invention can normally be used for the purpose of identification. The mark can not be erased by commonly available chemicals/solvents or by mechanical abrasion. The composition of the present invention has potential use particularly in the elections for putting identification mark on the back of the fore finger of the voter, so that impersonation is eliminated Different colouring agents, both synthetic and natural, have long been used for putting identification marks, but all of them can be removed by some chemical or the other. A few of them exhibit greater resistance to attack from chemicals. 'India Ink' consisting of finely divided lamp black suspended in gelatin and gum arabic has long been used as permanent marking composition, but this has also been found susceptible to removal by certain organic solvents like acetone, benzene and ether. The alkaloid present in the seed of 'bhilawa' plant has traditionally been used for marking fabrics, but this can also be removed by acids such as hydrochloric acid, acetic acid etc. Coal tar thinned with naphtha and pine soot has been used for marking cotton and linen. For putting a permanent mark on the skin method of 'tattooing', has been used , but the process is painful and cumbersome to use. It has been reported ( Carleon Ellis,"Printing Inks, Reinhold Publishing Corporation, New York, 1940, p-398-399.) that permanent mark can also be obtained by a composition made by adding potassium ferrocynide to normal ink. The application of hydrochloric acid to such a mark results in the formation of 'Prussian blue'. The product consisting of potassium chlorate, tartaric acid and aniline coupled with copper sulphate gives a permanent mark. A combination of 'hematin' extract, potassium dichromate, tannin and ferric chloride in dilute hydrochloric acid has also been used for similar purposes. Indelible ink used for putting a mark on the body of the voter during the elections contains silver nitrate which reacts with the skin to impart a permanent mark. The reaction of silver with the skin is, however, slow and takes around two to three hours to develop a permanent mark. This leaves scope for tampering with the mark for its removal. To reduce this time interval, the prepartion of indeHabte ink which will produce instantaneous mark on application has been carried out ( Indian Patent 157565). This consists of separate solutions of Silver nitrate and propyl gallate. Silver nitrate solution is applied first followed by the application of propyl gallate solution. Although it results into a permanent mark, the method of application is not as convenient as a single step process. It has been observed that the composition used for putting the identification mark used in the elections currently, suffers from many other disadvangages. A freshly applied mark is susceptible to removal since silver nitrate takes longer time to react with the substrate, hence can be erased by some chemicals. The removal is easier at the initial stages as the mark applied takes considerabale time for drying. Although high concentration such as 27% by weight of silver nitrate is used, it still takes longer time for completion of reaction with the skin of the individual and also requires the presence of sunlight. There is therfore an urgent need to develop a composition which is useful for making a permanent mark on a substrate probably useful for making a permanent mark for election purposes. The main objective of the present invention is to provide a composition useful for making a permanent mark on a substrate which has an improved performance over the existing indellible inks and drawbacks thereof are overcome. Another object is to provide a composition which can be applied in one step. Yet another object is that the appearance of the mark using the composition of the present invention should be instantaneous and quick drying so that the mark once applied should not be easily removed. Still another object of the present invention is that the chemicals used should not be corrosive or harmful to thesubstrate (human skin) and should not create any environmental problem. The principle by which the present invention has been developed is based on the reaction of the organic reagent like brilliant green with silver nitrate dissolved in a low vapour pressure solvent. The colour of the mark using the composition of the present invention can also be changed from an initial green, red, blue violet etc. to black within the chosen time by the judicious selection of organic compound like brilliant green, para rosaniline hydrochloride etc. The composition of the present invention when applied on a substrate, such as human skin/ nail, an oxidation reduction reaction takes place due to the presence of dye. This reaction may be enhanced by incorporating a sensitising agent. The mark made by using the composition of the present invention is less susceptible to removal by chemicals and solvents. Moreover, the change in the colour of the initial mark can be used to ascertain the duration of its application. This can be used as an additional step to eliminate impersonation. Suitable combinations of chemicals have been experimented to realize different colours such as blue, green and red. Accordingly, the present invention provides a process for the preparation of composition useful for making a permanent mark on a substrate which comprises; reacting 5- 30% by wt. of silver nitrate with 0.2-2% by wt. of dye capable of reducing silver nitrate and selected from brilliant green, safranin, methylene blue, para rosaniline, catechol violet, janus green or their mixture, adding 0-0.05% by wt. of sensitising agent such as herein described, adding 70-95% by wt. of solvent consisting of a mixture of water and organic solvents such as herein described in a ratio of 1:9 to 1:1 by volume to obtain the said composition. The dyes used may be such as brilliant green, safranin, methyleneblue, para rosaniline, catechol violet, Janus green. The organic solvents used in combination with water may be such as acetone, methanol, rectified spirit or combination thereof. The sensitizing agent used may be such as krytocyanine, potassium bromide. The mark appearing on the application of the composition of the present invention displays a desired colour for desired duration of time and then gradually turns black. The marking composition should normally be stored in amber coloured glass or opaque plastic containers. The application is essentially a one step process and the appearance of the coloured mark is instantaneous. The following examples are given by way of illustration and should not be construed to limit the scope of the present invention. Example 1 10 gms of silver nitrate and 1 gm of brilliant green are dissolved in 10 ml of water and 40 ml of methanol and the volume is made to 100 ml with acetone. The composition when applied to a substrate (human skin), a mark is formed instantaneously which is initially green but gradually changes to black. The duration of green mark is upto 12 hours. Example 2 15 gms of silver nitrate and 0.5 gm of safranin are dissolved in 20 ml of water and 30 ml of rectified spirit. The volume is made to 100 ml with acetone. The composition when applied on a substrate (human skin),the mark appears instantaneously which is initially red but gradually changes to black. Example 3 12 gmof silver nitrate and 1 gm of methylene blue are dissolved in 15 ml water and 30 ml methanol. 10 mgm. of potassium bromide is added and the volume made to 100 ml with acetone. The composition when applied on a substrate (human skin), the mark appears instantaneouslyl which is initially blue but gradually changes to black. Example 4 20 gm of silver nitrate and 0.5 gm of para-rosaniline hydrochloride are dissolved in 20 ml of water and 40 ml of methanol. 10 mgm. of krytocyanine is added to it and the volume made to 100 ml with acetone. The composition when applied on a substrate (human skin), the mark appears instantaneously which is initially red but gradully changes to black. Example 5 10 gm of silver nitrate, 0.75 gm of p-rosaniline hydrochloride and 20 mgm. of catechol violet are dissolved in 12 ml of water and 50 ml of rectified spirit. The volume is made to 100 ml with acetone. The composition when applied on a substrate (human skin), the mark appears instantaneously which is initially reddish-violet but gradually changes to black. Example 6 5 gm of silver nitrate and 1 gm of Janus green are dissolved in 10 ml of water and 40 ml of methanol. The volume is made to 100 ml with acetone. The composition when applied on a substrate (human skin), the mark appears instantaneously but initially appears green which gradually changing to black. The main advantages are: The composition of the present invention is quite stable and is easy to make. It is cheaper in cost and quicker in drying. It is made from commonly available chemicals. We Claim: 1. A process for the preparation of composition useful for making a permanent mark on a substrate which comprises; reacting 5- 30% by wt. of silver nitrate with 0.2-2% by wt. of dye capable of reducing silver nitrate and selected from brilliant green, safranin, methylene blue, para rosaniline, catechol violet, janus green or their mixture, adding 0-0.05% by wt. of sensitising agent such as herein described, adding 70-95% by wt. of solvent consisting of a mixture of water and organic solvents such as herein described in a ratio of 1:9 to 1:1 by volume to obtain the said composition. 2. A process as claimed in claim 1 wherein the silver nitrate used is of commercial/lab grade. 3. A process as claimed in claims 1-2 wherein the sensitizing agents used are krytocyanine or potassium bromide. 4. A process as claimed in claims 1-3 wherein the organic solvents used in combination with water are selected from acetone, methanol, rectified spirit or combination thereof. 5. A process for the preparation of composition useful for making a permanent mark on a substrate substantially as herein described with reference to the examples.

Full Text

This invention relates to a process for the preparation of composition useful for making a permanent mark on a substrate. The mark applied using the composition of the present invention can normally be used for the purpose of identification. The mark can not be erased by commonly available chemicals/solvents or by mechanical abrasion. The composition of the present invention has potential use particularly in the elections for putting identification mark on the back of the fore finger of the voter, so that impersonation is eliminated
Different colouring agents, both synthetic and natural, have long been used for
putting identification marks, but all of them can be removed by some chemical or the
other. A few of them exhibit greater resistance to attack from chemicals. 'India Ink'
consisting of finely divided lamp black suspended in gelatin and gum arabic has long
been used as permanent marking composition, but this has also been found susceptible
to removal by certain organic solvents like acetone, benzene and ether. The alkaloid
present in the seed of 'bhilawa' plant has traditionally been used for marking fabrics, but
this can also be removed by acids such as hydrochloric acid, acetic acid etc. Coal tar
thinned with naphtha and pine soot has been used for marking cotton and linen. For
putting a permanent mark on the skin method of 'tattooing', has been used , but the
process is painful and cumbersome to use. It has been reported ( Carleon Ellis,"Printing
Inks, Reinhold Publishing Corporation, New York, 1940, p-398-399.) that permanent mark
can also be obtained by a composition made by adding potassium ferrocynide to
normal ink. The application of hydrochloric acid to such a mark results in the formation of
'Prussian blue'. The product consisting of potassium chlorate, tartaric acid and aniline
coupled with copper sulphate gives a permanent mark. A combination of 'hematin'
extract, potassium dichromate, tannin and ferric chloride in dilute hydrochloric acid has also been used for similar purposes.
Indelible ink used for putting a mark on the body of the voter during the elections contains silver nitrate which reacts with the skin to impart a permanent mark. The reaction of silver with the skin is, however, slow and takes around two to three hours to develop a permanent mark. This leaves scope for tampering with the mark for its removal. To reduce this time interval, the prepartion of indeHabte ink which will produce instantaneous mark on application has been carried out ( Indian Patent 157565). This consists of separate solutions of Silver nitrate and propyl gallate. Silver nitrate solution is applied first followed by the application of propyl gallate solution. Although it results into a permanent mark, the method of application is not as convenient as a single step process.
It has been observed that the composition used for putting the identification mark used in the elections currently, suffers from many other disadvangages. A freshly applied mark is susceptible to removal since silver nitrate takes longer time to react with the substrate, hence can be erased by some chemicals. The removal is easier at the initial stages as the mark applied takes considerabale time for drying. Although high concentration such as 27% by weight of silver nitrate is used, it still takes longer time for completion of reaction with the skin of the individual and also requires the presence of sunlight.
There is therfore an urgent need to develop a composition which is useful for making a permanent mark on a substrate probably useful for making a permanent mark for
election purposes.
The main objective of the present invention is to provide a composition useful for making a permanent mark on a substrate which has an improved performance over the existing indellible inks and drawbacks thereof are overcome.
Another object is to provide a composition which can be applied in one step.
Yet another object is that the appearance of the mark using the composition of the present invention should be instantaneous and quick drying so that the mark once applied should not be easily removed.
Still another object of the present invention is that the chemicals used should not be corrosive or harmful to thesubstrate (human skin) and should not create any environmental problem.
The principle by which the present invention has been developed is based on the reaction of the organic reagent like brilliant green with silver nitrate dissolved in a low vapour pressure solvent. The colour of the mark using the composition of the present invention can also be changed from an initial green, red, blue violet etc. to black within the chosen time by the judicious selection of organic compound like brilliant green, para rosaniline hydrochloride etc.
The composition of the present invention when applied on a substrate, such as human skin/ nail, an oxidation reduction reaction takes place due to the presence of dye. This reaction may be enhanced by incorporating a sensitising agent.
The mark made by using the composition of the present invention is less susceptible to removal by chemicals and solvents.
Moreover, the change in the colour of the initial mark can be used to ascertain the duration of its application. This can be used as an additional step to eliminate impersonation. Suitable combinations of chemicals have been experimented to realize different colours such as blue, green and red.
Accordingly, the present invention provides a process for the preparation of composition useful for making a permanent mark on a substrate which comprises; reacting 5- 30% by wt. of silver nitrate with 0.2-2% by wt. of dye capable of reducing silver nitrate and selected from brilliant green, safranin, methylene blue, para rosaniline, catechol violet, janus green or their mixture, adding 0-0.05% by wt. of sensitising agent such as herein described, adding 70-95% by wt. of solvent consisting of a mixture of water and organic solvents such as herein described in a ratio of 1:9 to 1:1 by volume to obtain the said composition.
The dyes used may be such as brilliant green, safranin, methyleneblue, para rosaniline, catechol violet, Janus green. The organic solvents used in combination with water may be such as acetone, methanol, rectified spirit or combination thereof. The sensitizing agent used may be such as krytocyanine, potassium bromide.
The mark appearing on the application of the composition of the present invention displays a desired colour for desired duration of time and then gradually turns black. The marking composition should normally be stored in amber coloured glass or opaque plastic containers. The application is essentially a one step process and the appearance of the coloured mark is instantaneous.
The following examples are given by way of illustration and should not be construed to limit the scope of the present invention.
Example 1
10 gms of silver nitrate and 1 gm of brilliant green are dissolved in 10 ml of water and 40 ml of methanol and the volume is made to 100 ml with acetone. The composition when applied to a substrate (human skin), a mark is formed instantaneously which is initially green but gradually changes to black. The duration of green mark is upto 12 hours.
Example 2
15 gms of silver nitrate and 0.5 gm of safranin are dissolved in 20 ml of water and 30 ml of rectified spirit. The volume is made to 100 ml with acetone. The composition when applied on a substrate (human skin),the mark appears instantaneously which is initially red but gradually changes to black.
Example 3
12 gmof silver nitrate and 1 gm of methylene blue are dissolved in 15 ml water and 30 ml methanol. 10 mgm. of potassium bromide is added and the volume made to 100 ml with acetone. The composition when applied on a substrate (human skin), the mark appears instantaneouslyl which is initially blue but gradually changes to black.
Example 4
20 gm of silver nitrate and 0.5 gm of para-rosaniline hydrochloride are dissolved in 20 ml of water and 40 ml of methanol. 10 mgm. of krytocyanine is added to it and the volume made to 100 ml with acetone. The composition when applied on a substrate (human skin), the mark appears instantaneously which is initially red but gradully changes to black.
Example 5
10 gm of silver nitrate, 0.75 gm of p-rosaniline hydrochloride and 20 mgm. of catechol violet are dissolved in 12 ml of water and 50 ml of rectified spirit. The volume is made to 100 ml with acetone. The composition when applied on a substrate (human skin), the mark appears instantaneously which is initially reddish-violet but gradually changes to black.
Example 6
5 gm of silver nitrate and 1 gm of Janus green are dissolved in 10 ml of water and 40 ml of methanol. The volume is made to 100 ml with acetone. The composition when applied on a substrate (human skin), the mark appears instantaneously but initially appears green which gradually changing to black.
The main advantages are: The composition of the present invention is quite stable and is easy to make. It is cheaper in cost and quicker in drying. It is made from commonly available chemicals.

We Claim:
1. A process for the preparation of composition useful for making a permanent mark on a substrate which comprises; reacting 5- 30% by wt. of silver nitrate with 0.2-2% by wt. of dye capable of reducing silver nitrate and selected from brilliant green, safranin, methylene blue, para rosaniline, catechol violet, janus green or their mixture, adding 0-0.05% by wt. of sensitising agent such as herein described, adding 70-95% by wt. of solvent consisting of a mixture of water and organic solvents such as herein described in a ratio of 1:9 to 1:1 by volume to obtain the said composition.
2. A process as claimed in claim 1 wherein the silver nitrate used is of commercial/lab grade.
3. A process as claimed in claims 1-2 wherein the sensitizing agents used are krytocyanine or potassium bromide.
4. A process as claimed in claims 1-3 wherein the organic solvents used in combination with water are selected from acetone, methanol, rectified spirit or combination thereof.
5. A process for the preparation of composition useful for making a permanent mark on a substrate substantially as herein described with reference to the examples.

Documents:

1407-del-1996-abstract.pdf

1407-del-1996-claims.pdf

1407-del-1996-complete specification [granted].pdf

1407-del-1996-correspondence-others.pdf

1407-del-1996-correspondence-po.pdf

1407-del-1996-description (complete).pdf

1407-del-1996-form-1.pdf

1407-del-1996-form-2.pdf

1407-del-1996-form-4.pdf

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Patent Number

232725

Indian Patent Application Number

1407/DEL/1996

PG Journal Number

13/2009

Publication Date

27-Mar-2009

Grant Date

20-Mar-2009

Date of Filing

26-Jun-1996

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	PRAMOD KUMAR GUPTA	NATIONAL PHYSICAL LABORATORY, CSIR,DR.K.S.KRISHAN ROAD,NEW DELHI-110012,INDIA.
2	VASANTHA RAMAN	NATIONAL PHYSICAL LABORATORY, CSIR,DR.K.S.KRISHAN ROAD,NEW DELHI-110012,INDIA.
3	HAR PRAKASH NARANG	NATIONAL PHYSICAL LABORATORY, CSIR,DR.K.S.KRISHAN ROAD,NEW DELHI-110012,INDIA.
4	ERODE SUBRAMANIA RAJAGOPAL	NATIONAL PHYSICAL LABORATORY, CSIR,DR.K.S.KRISHAN ROAD,NEW DELHI-110012,INDIA.

PCT International Classification Number

C09D 061/02

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA