Secret (sympathetic ink). simple recipes

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FACTORY TECHNOLOGIES AT HOME - SIMPLE RECIPES
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Secret (sympathetic ink). Simple recipes and tips

Factory technologies - simple recipes

Directory / Factory technology at home - simple recipes

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sympathetic ink tend to give an invisible letter, which becomes noticeable only after special processing.

blue sympathetic ink

1st recipe:

Inscriptions made with a solution of 1 g of crystalline cobalt nitrogen salt or cobalt chloride in 25 g of distilled water are completely invisible; when the paper is slightly heated, they get a bluish color, which disappears when cooled.

Cobalt oxides 100 g;
Nitric acid 800 g.

Dissolve and mix with the solution:

Sodium chloride 100 g;
Distilled water 100 g.

What is written in ink is invisible. Show by heating over the lamp.

2st recipe:

Yellow blood salt 10 g;
Water 100 g.

Write with this solution. For development, moisten the paper with a solution:

Ferric chloride 200 g;
Water 500 cm3,

red sympathetic ink

Write with a diluted solution of chlorine gold and allow to dry. The writing disappears. After moistening the written places with a solution of tin salt, the inscriptions appear painted in purple-red color.

Disappearing Ink

Mix 50 g of iodine tincture with a teaspoon of dextrin and filter. Written in such ink will disappear in a day.

Author: Korolev V.A.

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