Colorless ink. How to make invisible ink

With friends, you will surely be interested in how to make invisible ink. There are several ways to write a secret message at home. All the methods below are absolutely safe and can be freely used in children's spy and scout games.

The simplest recipe

Perhaps in adventure books or children's detective stories you have already come across a mention that ordinary lemon juice can be used as a secret agent for spy messages. Unbelievable but true: to own experience to figure out how to make invisible ink, it is not at all necessary to own specific tools or technical sophisticated equipment. To conduct a fascinating experiment, you will need materials and items that can be found in any household, namely:

• half a lemon;
• water;
• the spoon;
• a bowl;
• cotton swab;
• White paper;
• lamp.

lemon magic

Once you have collected all the necessary items, you can proceed to the first experience. Later, you can proudly show your friends how to make invisible ink at home without any preparation. So:

• Squeeze some into a bowl and add a few drops of plain water.
• Mix juice and water using a spoon.
• Dip a Q-tip in the mixture and write your message on white paper.
• Wait for the juice to dry and become completely invisible.
• When you're ready to read or show your secret message, heat the paper by holding it close to the light bulb.

How it works

Lemon juice is organic matter, which oxidizes and acquires Brown color when heated. The juice is diluted with water so that when the resulting mixture is applied to paper, the letters and symbols practically disappear from the surface. No one will even guess that something is written on the leaf until you heat up the message. Other substances work on the same principle - for example, orange juice, honey, milk, onion juice, vinegar and wine. If you're wondering how to make invisible ink at home in other ways, try doing some chemistry experiments or looking at spy liquids under ultraviolet light.

Experiments with soda

A quick chemical experiment can be organized in just a few minutes if you have a common baking soda. What's more, science knows at least two ways to make invisible ink from this inexpensive powder. Try the following:

• Mix baking soda with water in equal proportions.
• Using a Q-tip, toothpick, or paintbrush, write a message on white paper using the baking soda solution as ink.
• Wait for the decal to dry.
• The first way to read the secret message is to heat the paper - for example, under a light bulb, as is the case with lemon juice. The lines will turn brown.
• The second way is much more interesting. To bring it to life, paint over all the paper with black grape juice. The message will appear in the form of letters in a contrasting color.

Hints

If you have already figured out how to make invisible ink, pay attention:

• If you prefer heat as a way to develop your message, be careful not to ignite the paper - don't use halogen bulbs.
• Baking soda and grape juice interact with each other in an acid-base reaction, producing changes in the color of words and letters.
• The solution can be made weaker by adding one part baking soda to two parts water. This will not affect the final effect.
• If you want to make the color change more vivid and obvious, use grape concentrate instead of regular juice.

other methods

Those who are interested in how to make invisible ink will surely like the idea of ​​using many different substances as the main material for secret correspondence. Indeed, many substances are suitable for espionage and intelligence correspondence, but secret agents need to remember which reagents each of them manifests with. If you forgot the perfect reagent, don't despair, most of the substances listed below can be developed with acid. So, just paint the secret paper with lemon juice. Some messages are revealed when heated, so if you already know how to make invisible ink and write a magic letter with it, keep a source of heat with you.

Ideal for experimenting with secret correspondence:

• phenolphthalein (demonstrated by soda);
• vinegar or diluted acetic acid(you can see the message by dipping it in a red cabbage broth);
• table salt (silver nitrate is enough for developing);
• (you will need sodium iodide or;
• ferrous sulfate (manifested by soda);
• corn or potato starch (you need an iodine solution to read).

Now you know a lot about how to make invisible ink - you can go explore!

Since ancient times, mankind has tried to invent invisible or, as they are also called, sympathetic ink, which are not visible to the eye in normal conditions, but they begin to appear after exposure to any chemical elements, heating, ultraviolet rays. They were used to send secret messages, to keep important information, secret correspondence.

In ancient times, these were commonly available substances that could be found in every home. For example, cryptography, carried out with the help of milk, lemon juice, rice water, wax, apple and onion juice, swede juice, enjoyed great success. Later, options for making sympathetic ink appeared using aspirin tablets, copper sulfate, iodine, and washing powder.

Modern UV inks

Science does not stand still, so in our time you will no longer surprise anyone with invisible industrial ink. Compounds that glow under ultraviolet lamps are very popular. There are even pens with UV ink on sale, which can be found in spy shops.

An alternative to such a pen can be invisible anti-counterfeiting paints and pigments. They are powdered substances that can be used to mark banknotes, securities, clothes. In daylight, the powder is completely indistinguishable, but in ultraviolet light, every grain or powder becomes noticeable.

How to make invisible fluorescent ink at home

A good fluorescent ink can be a regular laundry detergent containing optical brighteners. Having diluted the powder with a small amount of water, you can begin to write a secret message. The dried solution will not leave prints on paper, but it will be perfectly visible in the light of an ultraviolet lamp.

Also can be purchased separately. As a rule, they are used to give whiteness with a bluish tint to clothes, fabrics, paper intended for printer printing. The powder can also be used to create sympathetic ink. These inks show up on all types of paper.

Another way to make invisible ink is to use aspirin tablets and alcohol. In a small amount of alcohol, 2-3 aspirin tablets should be dissolved. If a precipitate remains during the dissolution, then the liquid should be filtered. After that, you can start secret writing. Such ink does not glow on all types of paper, this method is not applicable if you write on printer paper.

You can also use the following preparations to prepare ink, which you can try to purchase at a pharmacy:

• curcumin;
• quinine sulfate;
• tripoflamin.

Fluorescein sodium salt can also be used, but its native color may stand out on white paper after application, so this ink is not considered invisible.

Recipes for making invisible ink. Ways of their manifestation.

Cryptography appeared in the first century BC. These were the secret records of the pharaohs. Since then, much has changed in cryptography. They began to use for this not only the juice of plants and milk, but also specially designed chemical inks. Basically, this type of secret writing is aimed at diplomatic negotiations or secret correspondence.

Sympathetic inks are special compounds that, when applied to paper under normal conditions, become invisible. Under certain conditions, entries appear. This can be both treatment with reagents and a change in temperature. These inks often develop when heated. Initially, this method was used for secret correspondence. Now this is a kind of shorthand method.

Such ink is quite simple to make at home. Such experiments will be interesting for children. First of all, you need to figure out what you are going to make ink from. There are many components and options.

Ink options:

• Milk
• Cobalt
• washing powder
• Lemon juice
• Aspirin

These inks are manifested by salts that contain iron. It can be bartholite salt or iron sulphate. The recipe for making ink is simple.

Instruction:

• Dissolve an aspirin tablet in 20 ml injections. It is better to turn it into powder initially
• After that, dip a brush or toothpick in the liquid and write a letter
• Let it dry completely, you can put it in an envelope

Oddly enough, invisible ink can be made from lemon juice.

Instruction:

• Squeeze some lemon juice into a bowl and add 5 drops of water
• After that, dip a cotton swab into the juice and write a letter
• Let the juice dry completely. Keep away from sunlight
• The ink needs to be slightly warmed up to develop. This can be done with an iron or a light bulb.

Inscriptions made in this way can be viewed using UV light. A fluorescent lamp or flashlight will do.

Instruction:

• Dissolve 10 g of washing powder in 100 ml of water. Mix the ingredients very carefully.
• It is necessary that the grains of the powder dissolve
• Dip your brush in the solution and write on the paper
• Dry without using the sun

This ink was used by the ancient Chinese for inscriptions.

Instruction:

• Boil rice in water. Can you make porridge out of it?
• After that, moisten the brush in a viscous broth and apply the inscription
• Let the letter dry in the shade
• Use iodine to develop ink
• In places of inscriptions, it will turn blue, since rice contains starch.

This is the most good recipe, as the inscriptions after development become bright and saturated.

Instruction:

• Dissolve a pinch of cobalt chloride in 20 ml of water
• Stir the solution thoroughly and soak the brush in it.
• Apply the lettering to the sheet and let it dry completely.
• In order to develop the inscription, it is necessary to heat the letter with an iron or a light bulb.

An easy way from a product that is available in almost every refrigerator.

Instruction:

• Pour some milk into a glass and dip your brush into it.
• Write on paper and let dry.
• Do not dry in direct sunlight
• To develop, the letter needs to be heated.

For applying beeches, a concentrated solution is used.

Instruction:

• Boil water and dissolve 10 g of sodium bicarbonate in 100 ml of boiling water
• It is necessary to achieve complete dissolution of the crystals
• Dip a wand into the cooled solution and write secret information
• Dry the paper in the shade. Heat the letter to develop

These are special inks, as they are visible at first, and after 1-2 days they completely disappear.

Instruction:

• In half a teaspoon of dextrin, we introduce 30 ml of a solution of iodine in alcohol, and pour it through gauze folded several times
• Filtered "ink" of blue color now write information
• In a day, thanks to the volatility of iodine, the text will completely and irrevocably disappear.
• To make the inscription visible again, go over the paper with a swab dipped in iodine solution.

This method was used in the Middle Ages. Also, the method was popular among the inquisitors.

Instruction:

• Add a pinch of copper sulfate salt to 30 ml of water
• Achieve complete dissolution of crystals
• Dampen the brush with the mixture and apply the inscription
• Let the solution dry in a shady area.
• To develop the inscription, hold the sheet over ammonia
• Due to the formation of ammonium salt, the inscription will turn blue

Milk, cobalt chloride and lemon juice react to heating.

Instruction:

• Put the letter on a clean sheet and cover with another white sheet.
• Heat the sheet with an iron
• You can develop a letter using a light bulb
• Just hold a sheet of paper over a lamp or table lamp

How to make an invisible ink pen? How to refill a pen with invisible ink?

You can use a ballpoint pen or fountain pen for this. With a pen, everything is simple. It is necessary to pour one of the secret solutions into the ink compartment and boldly start writing.

Instructions for making an invisible ink pen:

• Take a ballpoint pen with ink that has run out of ink.
• Rinse thoroughly with alcohol, after removing the metal rod
• It is necessary to achieve complete evaporation of alcohol and the purity of the metal nozzle
• Install the nozzle in place, and pour invisible ink into the tube using a syringe
• You can start writing

As you can see, with the help of simple manipulations, invisible ink can be made. This will amuse your children.

VIDEO: Invisible ink

Well, who in childhood did not invent secret ciphers? It's so interesting to send a message to a friend that none of the "enemies" can read 🙂 My daughter and I decided to play spies and did it ourselves invisible ink .

And it all started with a magic box Superprofessor. Qiddycome. A series of the best chemical experiments: "Fire ink and prank succeeded" .

invisible ink

Invisible or sympathetic ink - These are liquids that, when written, do not leave a colored trace on paper. You can read the inscription only by processing the paper in a special way.

How to make invisible ink was described by Philo of Alexandria in the 1st century AD.

"Invisible milk powder ink" - experiment #1

At times Russian revolution secret messages were often written in ordinary letters between the lines. It was the simplest invisible ink.

To make them you need to take:

• dry milk - 1 tsp
• water - 50 g
• piece of paper
• brush
• iron (or candle, or table lamp)

The course of the experiment "Invisible ink" - method number 1

1. Dissolve milk powder in water by stirring thoroughly.

2. Dip the brush into the resulting solution and write a secret message.

3. We are waiting for the invisible ink to dry. For greater secrecy, we write a deceptive text with a regular pen and send a letter.

4. To read the letter, you need to hold the paper over the lamp or iron it.

It turned out that writing with invisible ink is very difficult - they are really invisible 🙂 For reliability, I had to trace the letters blindly, so the inscription is fuzzy.

"Invisible Fresh Milk Ink" - Experiment #2

Olesya and I experimented and tried to write a message with regular milk (3.2% fat).

The result is almost the same as with the use of powdered milk, just do not bother with the search for powdered milk. If there is a "cow" - it's easy to write a secret message 🙂

"Invisible Copper Ink" - Experiment #3

This ink is more difficult to prepare, because you have to look for the ingredients:

• copper sulphate powder - 1. tsp. (5 mg)
• ammonia
• water (50 g)
• stick for stirring
• paper and brush

The course of the experiment "Invisible ink" - method number 3

1. Add copper sulfate powder to the water and mix thoroughly with a stick until a pale blue solution is obtained.

2. We dip the brush in a solution of copper sulfate and write a secret message.

3. We wait until the invisible ink dries and send it to its destination.

4. To read the secret message, pour 10-15 ml of ammonia into a glass and hold the paper over the glass until the invisible ink turns blue.

Since the ammonia “smells” very strongly, we tried to iron the message from invisible ink with blue vitriol. The letters also appeared, although not so clearly:

"Invisible Soda Ink" Experiment #4

This experiment can also be carried out in an ordinary kitchen.

For him you will need:

• warm water
• the spoon
• paper
• cotton swab
• iron (lamp or candle)

The course of the experiment "Invisible ink" - method number 4

1. Dissolve soda in water.

2. Dip a cotton swab in the soda solution and wring it out slightly.

3. Leave the message alone until completely dry.

4. We iron the paper or heat it over a lamp (candle)

Invisible soda ink gave a great result - perfect drying and excellent development of the letter.

Our impressions of invisible ink

Half of our kitchen was covered with drying secret messages:

And these are our secret letters already revealed:

Most of all we liked soda invisible ink . They dry quickly and are completely invisible. When the messages are heated, the writings with this ink are clearly visible.

Messages from copper sulphate unpleasant to show due to bad smell ammonia. We tried to develop them using an iron - it turned out 🙂 And yet we liked such invisible ink because of the easy development. In our ranking, they are in 2nd place.

Messages from fresh and dried milk dries to a slight sheen. When ironing, they appear heterogeneous. We ranked the invisible ink from fresh milk at 3rd place (availability), and the ink from powdered milk at 4th place.

That's how we learned to do with my daughter invisible ink . Now it's up to friends - we will teach them and we will exchange secret messages.

And you can also see VERY interesting chemical experience by volcanic eruption.

The use of invisible (sympathetic) ink is not only an integral part of children's spy games, but also original way Surprise your friends at a party or propose to your girlfriend. It is very simple to prepare them at home, and they contain the most common ingredients that are found in any home.

Usually, for the effective manifestation of such ink, a secret message is first written on paper, and another message is written on top in the usual way. This is how encrypted information was transmitted in ancient times.

There are several types of sympathetic ink, they are distinguished not only by composition, but also by the conditions under which the ink becomes visible.

Invisible ink at home using lemon

The recipe for invisible citric acid ink is one of the easiest and most affordable to prepare. All you need is half a lemon or liquid lemon acid, water, a deep plate, a brush and a sheet of white paper.

• First you need to squeeze the juice from the lemon into a deep plate and add not a large number of water. Dilute the lemon juice, in principle, is optional, but then the ink will initially be slightly visible on paper.
• Stir the contents of the dish.
• Wet the brush with the resulting liquid and write your message on white paper.
• Wait until the liquid is completely dry.
• When it's time to read the message, the piece of paper needs to be heated. Suitable for this table lamp, iron, candle or oven.

Due to the fact that lemon juice has the ability to oxidize when heated, it will change color to brown. By the same principle, ink prepared without lemon, but, for example, from onion juice or honey, will work.

invisible ink from soda

There are several options for making invisible ink from soda, but they are all easy to perform.

For the first recipe, you will need baking soda, warm water, a piece of paper, and a Q-tip or brush.

• Mix baking soda and water in a 1:1 ratio.
• Stir until the soda dissolves.
• Soak a cotton swab in the resulting liquid and write a secret message on paper.
• Wait until the inscription is completely dry.
• To demonstrate your message, you need to heat the sheet with a lamp or in any other way. However, do not forget about safety when working with heating elements so that the paper does not ignite. A container of plain water should be prepared in advance to extinguish the burning paper if the process does not go according to plan.

The second variation of the baking soda invisible ink recipe involves the use of grape juice to develop the cipher. Once the ink has been applied to the paper and dried, the sheet of paper does not need to be heated to develop the message. It is enough to dip a brush or cotton swab in grape juice and paint the paper until the symbols appear. This happens through the entry into chemical reaction soda and grape juice.

Invisible milk ink

Incredibly easy way to make invisible ink. The ingredients will require milk, a sheet of paper and a brush.

• Write a message on a piece of paper with a brush dipped in milk.
• Wait until the inscription dries well.
• To manifest the message, it is enough to gently heat a sheet of paper.

Invisible laundry detergent ink

Prepare for this recipe a small amount of washing powder, water, a sheet of paper, a brush, a deep plate and an ultraviolet lamp.

• Mix the powder with water, stir.
• Write an encrypted message on a piece of paper with a brush soaked in the solution.
• Let dry.
• To view the inscription, you need to turn off the light and bring an ultraviolet flashlight or lamp to the paper. The symbols will glow in the dark.

Invisible ink at home from starch

Cooking Ingredients:

Starch,

Small saucepan or bowl

tassel,

Paper,

An aqueous solution of iodine.

1) First you need to cook a starch paste. To do this, mix 2 parts of starch and 1 part of water in a ladle or saucepan. The resulting mass must be simmered a little over low heat until it warms up, while stirring thoroughly.

2) Allow the paste to cool.

3) Dip the brush in the resulting ink and write in large characters on a piece of paper.

4) Let dry.

5) To read the message, it is necessary to paint the paper with an aqueous solution of iodine. The lettering will turn bright purple.

Knowing the principle of the interaction of starch and iodine, this recipe can be slightly modified if there is no pure starch at home. Enough to cook thick rice porridge instead of paste, since rice contains a large amount of starch. Further actions do not differ from those described in the recipe with pure starch.

On sale there are also ready-made sets for preparing ink, as well as various pens filled with already prepared sympathetic ink. However, cook them yourself from simple and available funds It will be much more exciting not only for the child, but also for the adult.

Video on the topic of the article