Title of Invention

"A PROCESS FOR THE PREPARATION OF NOVEL FINGERPRINT MIXTURE"

Abstract

This invention relates to a process for the preparation of a novel finger print mixture to be used for finger prints on various surfaces comprising in the steps of:- preparing a solution of disodium phloxine B dye by dissolving 0.38 to 0.42 gram of disodium phloxine B dye in distilled water, preparing a solution of t-tetrabutylammonium iodide by dissolving 0.18-0.22 gram of t-tetrabutylammonium in distilled water, Admixing solution A to solution B vigorously.

Full Text

FIELD OF INVENTION This invention relates to a process for the preparation/ of a novel fingerprint mixture for detecting latent fingerprints on various surfaces, such as paper, porcelain, plastic, polythene, bakelite, glass and metallic. PRIOR ART Latent fingerprints impinged on various surfaces may be developed by a legion of techniques. The application of finely divided materials and the subsequent removal of excess powder by brushing, blowing or tapping is a universal method of detecting fingerprints on non-absorbent surfaces. The technique relies on the mechanical adherence of fingerprint powder to moisture and oily components of the skin ridge deposits. However, since moisture and oily components of sweat tend to evaporate within 48 hours or so, the powder method cannot be used to detect old prints. Further, several powder formulations are toxic in nature. The ninhydrin reagent fixes the amino acid constituents of finger sweat and gives prints on old samples. The disadvantage of this technique is that. ninhydrin has to be dissolved in an organic medium. Since these days oil based inks are more often used, spraying an organic solvent on a document may despoil the calligraphic script. Latent fingerprints may also be developed by a solution of silver nitrate. This reagent reacts with the sodium chloride constituent of sweat. By a simple ionic reaction, silver chloride is formed which on exposure to sunlight, decomposes into finely divided silver that deposits on the ridges giving black imprints. The silver nitrate method suffers from the drawback that the reagent leaves a black mark on the users hands, which takes a very long time to fade out. Moreover, silver nitrate is an expensive reagent and therefore the method is not cost-effective. Iodine fumes render visibility to latent prints by fixing fatty acid constituents of sweat. However, the prints obtained by iodine fuming are not permanent and tend to fade out with time. The toxicity of iodine also limits the use of this method. OBJECTS OF THE PRESENT INVENTION An abject of the present invention is to propose a novel fingerprint preparation based on phloxine B dye and to a process for the preparation thereof. Another object of this invention is to propose a fingerprint preparation and a process there for which obviates the disadvantages associated with those of the prior art. Yet another object of this invention is to propose a fingerprint preparation and a process there for which develops clear and sharp prints, visible even to the naked eye, on a wide range of surfaces, including lamination and polythene sheets. Still another object of this invention is to propose a fingerprint preparation which is non-toxic. A further object of this invention is to propose a fingerprint preparation which is fluorescent and therefore can develop weak prints on various surfaces. An even further object of the present invention is to propose a fingerprint preparation that can render visibility to latent fingerprints in a period as short as 2-3 minutes. DESCRIPTION OF THE PRESENT INVENTION According to this invention there is provided a A process for the preparation of a novel finger print mixture to be used for finger prints on various surfaces comprising in the steps of:- a) preparing a solution of disodium phloxine B dye by dissolving 0.38 to 0.42 gram of disodium phloxine B dye in distilled water, b) preparing a solution of t-tetrabutylammonium iodide by dissolving 0.18-0.22 gram of t-tetrabutylammonium in distilled water, c) Admixing solution A to solution B vigorously with glass rod to form the finger print mixture. Further according to this invention there is provided a process for the preparation of a fingerprint preparation for detecting latent fingerprints on various surfaces which comprises in the steps of admixing a first solution to a second solution, the first solution being a disodium phloxine B dye solution having a concentration of 0.38 % to 0.42%, the second solution being a t-tetrabutylammonium iodide solution having a concentration of 0.18% to 0.22%. The present fingerprint spray contains 0.38-0.42 % phloxine B dye and 0.18-0.22 % of t-tetrabutylammonium iodide. It is prepared in the following steps: 1. Weigh out 0.38-0.42 gram of disodium phloxine B dye in a 150 ml beaker. 2. Dissolve the disodium phloxine B dye in 25 ml of distilled water (Solution A). 3. Weigh out 0.18-0.22 gram of t-tetrabutylammonium iodide in a 150 ml beaker. 4. Suspend the t-tetrabutylammonium iodide in 25 ml of distilled water (Solution B). 5. Add solution A to solution B. Add 50 ml of distilled water to the mixture. Stir vigorously with a glass rod. 6. Store the formulation in a tightly stoppered bottle. The process for the preparation of the spray formulation for detecting latent fingerprints is now described with reference to the ensuing examples. EXAMPLE 1 A piece of white? bond paper impinged with a latent fingerprint was sprayed with a solution containing 0.40 g phloxine B and 0.20 g t- tetrabutylammonium iodide dissolved in 100 ml of distilled water. After two minutes, the paper was taken out and washed under a gentle stream of distilled water. On drying, a clear and sharp ridge pattern was obtained. EXAMPLE-2 A solution containing 0.38 g phloxine B and 0.20 g t-tetrabutylammonium iodide dissolved in 100 ml of distilled water was sprayed on a latent fingermark V imprinted on a plastic bottle. After two and a half minutes, the excess solution was washed under a gentle stream of distilled water. Clear and sharp fingerprints were visualized. EXAMPLE-3 Dissolved 0.42 g phloxine B and 0.18 g t— tetrabutylammonium iodide in 100 ml distilled water. Sprayed the solution on a bakelite switchboard, bearing the sample print. After three minutes, it was washed under a gentle stream of distilled water. Clear and sharp finger ridge pattern was rendered visible. EXAMPLE-4 A test solution containing 0.39 g phloxine B and (3.2.1 g t-tetrabutylammonium iodide, dissolved in 100 ml distilled water was sprayed on a porcelain saucer bearing the latent fingerprint. After two and a half minutes, the item was washed under a gentle stream of distilled water, clear and sharp fingerprints were observed. ADVANTA6ES OF PRESENT INVENTION The fingerprint spray prepared for the present invention offers the following advantages: 1. It is non-toxic. Phloxine B is an analytical reagent and a biological stain. It is also used in cosmetics. 2. Since the solution is prepared in water, the spray may be used on documents scripted with bal1-pen ink. 3. Phloxine B and t-tetrabutylammonium iodide are cheap and easily available reagents. Therefore, the method is cost—effective. 4. Phloxine B is a fluorescent dye. Therefore, weak prints may be developed under ultraviolet light. 5. It gives sharp and clear prints, visible even to the naked eye. The prints persist over prolonged periods of time. They may be developed on a wide variety of surfaces. 6. The fingerprints developed on paper do not get smudged on rubbing or scratching. 7. It gives good quality prints on lamination and polythene sheets. For developing prints on these surfaces, neutron activation analysis technique has to be used and this facility is not available in most forensic science laboratories in India. Fig.l of the enclosed drawing shows the chemical formula of phloxine B dye. Fig.2(a) to 2(c) show the sharp and clear prints obtained on paper, porcelain and plastic surfaces respectively. WE CLAIM: 1. A process for the preparation of a novel finger print mixture to be used for finger prints on various surfaces comprising in the steps of:- a) preparing a solution of disodium phloxine B dye by dissolving 0.38 to 0.42 gram of disodium phloxine B dye in distilled water, b) preparing a solution of t-tetrabutylammonium iodide by dissolving 0.18-0.22 gram of t-tetrabutylammonium in distilled water, c) Admixing solution A to solution B vigorously with glass rod to form the finger print mixture. 2. A process for the preparation of a novel finger print mixture thereof substantially as here in described and illustrated.

Documents:

347-del-1999-abstract.pdf

347-del-1999-claims.pdf

347-del-1999-correspondence-others.pdf

347-del-1999-correspondence-po.pdf

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

347-del-1999-drawings.pdf

347-del-1999-form-1.pdf

347-del-1999-form-19.pdf

347-del-1999-form-2.pdf

347-del-1999-form-3.pdf

347-del-1999-gpa.pdf