Invisible ink

How to make Invisible ink

Preparation of tannic acid

In the manufacture of inks tannic acid is mixed with ferrous sulpate forming ferrous tannate which is nearly colourless but is readily oxidized to black insoluble ferric tannate by atmospheric oxygen. Inks contain a protective colloid such as gum Arabic to make them more durable. A blue dye is also added in order to give the ink a dark colour. When ink marks are made upon paper the colour is at first due to the dye, but as soon as the ferrous tannate is oxidized an intense and lasting black colour is produced. Details of manufacture varied greatly with the type of ink being produced. 

How to make Blue Black Fountain Pen Ink 

 Material 

Tannic acid 75g Gallic acid 30g Ferrous sulphate 100g Hydrochloric acid (dilute) 75cm3 Gum Arabic 60g Carbolic acid 15g Phenol blue 15g Distilled water to make 3dm3 

 How to make Blue Black Ink 

This ink is used to write on the paper.It is most famous ink 

Preparation 

 Dissolve tannic and gallic acid in 150 cm3 of warm water. Dissolve ferrous sulphate and gum Arabic in 600cm3 distilled water. Add the hydrochloric acid to it and immediately mix the two solutions. Add the carbolic acid, phenol blue and sufficient water to produce 3dm3 solution. Keep aside for a fortnight and then filter. 

How to make Royal Blue Pen Ink 

 Ink blue A.S (colour) 15g Methyl violet 5g Ethylene glycol 20cm3 Acetone 10cm3 Phenol 1g Carboxy methyl cellulose 1000cm3 Dissolve carboxy methyl cellulose in distilled water and keep it ready for use. In another pot dissolve the colours in 200cm3 of warm distilled . When the colours have completely dissolved, filter the solution. Mix this solution with the carboxy methyl cellulose solution and add the remaining ingredients. Stir will and keep aside for 10 days, then filter. 

How to make Ink Used to Write on Glass Surface 

 With this ink we can write on the glass surface easily.Glass surface can destroy with common ink. Raw Material Chromic Oxide 10 parts Lead borate 05 parts Water 0.5 parts Glycerine 0.5 parts Alcohol 0.5 parts 

Method of Preparation

 An effective and permanent glass marketing ink is made by mixing 10 parts of chromic oxide with 5 parts of powdered lead borate, add this mixture to a solution containing water, alcohol and glycerine. After applying the ink with a pen, the glass is warmed in the yellow flameof a Bunsen burner then heated to red hot in a blue flame. The glass is finally allowed to cool using the yellow flame to lower the temperature gradually.

 How to make Invisible Ink 

Raw Materials 

Mercurous Nitrate 10 Parts Water 100 Parts Ammonia 30% 50 Parts 

Method of Preparation

 Dissolve 10 parts of mercurous nitrate in 100 parts of water. Write down with this solution on a white paper. On drying the solution, the writing will not be visible. Now add 5 parts of 30% ammonia solution in a jar. On putting the written statement over the jar of ammonia solution, the writing will be visible due to the formation of black precipitate.