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WATERCOLOR

 

In old books often names exotic dyes: red sandalwood, quercitron, Carmine, Sepia, sandal wood tree... Some of these dyes used today, but in very small quantities, mainly for the preparation of paints. Because natural dyes such beautiful names are derived from plants and animals, and this, as you know, is expensive and difficult. But natural dyes are very bright, durable, lightfast.

I'd be curious to check. But how? Sandal wood tree grows in South America, sandalwood in South Asia, Sepia extracted from cuttlefish, Carmine from cochineal (tiny insects)...

And still get natural dyes even at home, even in the middle of our country is possible. And in the usual plants include colorants, though not so bright and not so persistent. Our ancestors often used. And we will try to extract the dyes from plants, and then based on them will prepare water-soluble paints, known as watercolor. Naturally, the dyes that we will finish, should be well soluble in water.

All dyes will prepare the same way: grind plants or any part thereof and will long be boiled in water to make a concentrated broth. It should be fairly thick. Remove the dry dye we don't need anyway because we have to prepare the water-soluble paint.

Very important: take only those plants that are allowed to collect where you live; in no case do not pick plants that are protected in your area or country. And in any case, in order not to harm nature, limit the number of collected plants to a minimum.

Let's start with the red dye. It can be obtained from the stem of Hypericum (the broth should be acidified) or from the root of bedstraw, you May not know, the look of these plants. In this case, consult your biology teacher or rent in the library any book or vascular plants; they usually are given and descriptions of plants and their pictures.

Alder bark is put in water for a few days, and then prepare the decoction. Again you get red dye. It can also extract from the roots of sorrel, but in this case, do not forget to add to the finished broth a little aluminum alum - otherwise the color will be dull.

Of the known plants roots of Valerian (he, like St. John's wort, is an herbal plant) you can get the blue dye. To do this, the roots must first hold in liquid ammonia - water solution of ammonia. Blue dye can be extracted from the flowers of iokasti roots and bird of Grechesky.

The green dye is extracted from leaves of the Shamrock (also, incidentally, a medicinal herb). Not as bright, but nevertheless beautiful gray-green dye you extracted from the leaves and stems of the cuff; before cooking broth must carefully grind.

Yellow dye give many plants: dye Dyer, hazel (bark), olkhovidna buckthorn (bark, leaves, berries), bedstraw (flowers). From the fruit of the barberry is obtained a yellow dye with a lemon twist.

If boiled in water, dry the peel of onion, then brown dye different shades from almost yellow to dark brown. Another source of such dye - dry bark Zostera.

Berries blueberries and blackberries, as you might guess, contains purple dye. It is not very resistant, but it can be useful for watercolor paints. And from the stems and leaves of the herb are able to extract the dye orange.

How to get the black pigment? First, you can prepare a decoction of berries and roots funnel. But there is another way, more simple: add the iron sulfate to the one obtained earlier concoctions. Almost all teas contain tannins type of tannin (recall the experiments with tea), and in the presence of salts of divalent iron, they become black.

You have reserved a sufficient number of thick colorful concoctions? Then proceed to the main - producing watercolor. Its main component parts of the dye and water, but there are other prerequisites. First of all, those substances which bind the paint to the paper, such as gum Arabic or wood adhesives are substances with high viscosity. Next, the desired viscous substances, they will prevent the paint onto the paper, will force her to lie evenly; good for this, honey, syrup, glycerin. And the latest additive antiseptic and disinfectant agent. Because we are dealing with substances of vegetable origin, and their need to be protected from the action of microorganisms (fungi, which are going to want to eat our colors).

If you do not have gum Arabic, as adhesives it is best to take a cherry and a plum glue, incrustations on the trunks that can be collected directly from the trees - it's not their harm. However, such adhesives (more precisely,the gum in water, soluble with difficulty, but if you add a little acid, the dissolution will go much faster.

To paint each color cook 5-7 ml of adhesive approximately 50%concentration. Mix it with an equal amount of glycerin or about three times smaller amount of honey. Antiseptic will serve as phenol, 5 %solution called "carbolic acid" in pharmacies. This substance is very short, just a few drops.

All components of the future paint mix. The paint base is ready, not only the most important - dye. Add it last in thick broth, took him about the same as you got the basics for paint.

Here, actually, and the whole procedure. Now you might wonder why the paint turned out to be not solid in shops, it is sold in bars. However, the artists use and semi-liquid watercolor paints in tubes. Consistency, they just remind me of those colorful paints that you just made.

If you want to keep your paint, be sure to pour it in something flask, tightly sealed plastic tubes, otherwise the paint will soon dry up. And to work it as well as all sorts of other watercolor paints: soft brush, thick paper... However, among young chemists probably have young artists.

Before moving on to a new topic, I will give you another tip: try to paint the fabric. Because in the old days a large part of the vegetable dyes used for this purpose. Agree only this: do not put in the dye bath (and it can serve as a bowl or basin) good stuff. Experiment first with pieces of clean white cloth or yarn. And only if you make sure that the experience is successful, take any thing necessarily of the same fibers, on which you set for the experiment.

Before painting fabric, usually required etch - hold in a hot solution of any salt; for this purpose often take a solution of potassium alum. Holding the fabric or yarn in the stain for a few minutes, dip it in the broth dye, pre-filtered through cheesecloth and boil it. Accurate advice, how strong must be the broth, to give, unfortunately, not because the two apparently identical plants can contain different amounts of the coloring matter. So h the concentration and processing time have to be chosen empirically.

To name a few plant from which it is possible to get a good coloring broths for fabric. Let's start with the already mentioned onion peel. In her decoction of the fabric will become yellow-red, if you etch it with alum, and green when stained with iron sulphate. Onion peels used since ancient times for dyeing wool and flax.

From the leaves and stems of potato is also possible to prepare the dye. Their broth stain fabric in lemon color, if the fabric is pre-treated with a solution of any salt of tin. A decoction of rhubarb will give fabric, etched with a solution of iron sulphate, swamp color.

For dyeing wool can be used decoctions of the bark of trees. So, alder bark will paint coat in dark red color, bark ash in blue. Wood wild pear contains brown dye the wool before dyeing it is necessary to etch in aqueous solution of any salt of bismuth). In the birch leaves are gray-green dye, however, it is not very effective.

In the old days, rarely, but still dyed wool with a solution of coffee, only raw, to get the green color. Try this dye, the benefit of raw coffee beans need quite a bit. They need to grind and boil with the addition of washing soda, and coat before putting it in the broth, etch in a hot solution of alum.

If this lesson is to your taste, check for yourself coloring effect other plants in combination with different Bates. It is possible that you will find any unknown or completely forgotten the combination, and the colouring will be extremely beautiful.

O. Holguín. "Experiments without explosions"
M., "Chemistry", 1986

 

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Ilya
2014-03-05 20:22:05
I am very grateful!!
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