Coloring pigments for concrete. Pigment for concrete by own hands

More recently, concrete could be only one color - dull and gray. Today, thanks to advanced technological developments, architects and designers can use a concrete compound painted in any desired color for the construction of structures. Modern paints and pigments for concrete are used for painting a wide variety of surfaces. In this article we will consider the types of modern pigments for painting concrete surfaces, as well as the peculiarities of their use.

What it is?

Pigments for concrete are special powder additives, due to which it is possible to give the necessary color to the solution or the finished concrete product. Such colorants after drying the painted surface do not dissolve in water, oil and other liquids. In addition, provided good quality, they are fairly resistant to ultraviolet (sunlight) and rain-washing. Pigment of each color has the ability to selectively reflect the flow of daylight. A coloring substance of a particular color absorbs and reflects only strictly defined waves of the visible spectrum. There are only two exceptions: thus, the pigment for white concrete reflects almost all the spectrum of color falling on it, but the black dye, on the contrary, absorbs most of the spectral waves.

Classification

Pigments used for coloring concrete are classified by origin on:

1. Organic pigments :

- yellow;

- scarlet;

- Red;

- Light blue;

- green;

- purple;

- Pink;

- burgundy;

- artificial cinnabar.

2. Mineral - pigments for concrete inorganic powder.

• Natural:

- kaolin;

- iron wax ;

- Manganese peroxide;

- a piece of chalk;

- graphite;

- Lime;

- Umber;

- ocher.

• Artificial:

- chromium oxide;

- Carbon black;

- zinc crowns and greens;

- Burnt umber;

- Lithopone is dry;

- azure paint;

- Zinc, titanium and lead white.

3. Metal:

- the bronze is golden;

- aluminum powder;

- Zinc dust.

To obtain natural dry pigments for concrete, mechanically grind various natural materials, and for the production of artificial dyes, mineral raw materials, for example, ocher, are subjected to heat treatment.

Modern dyes are produced not only in the form of dry powders, but also in the form of emulsions, concentrated pastes and microcapsules.

Main characteristics

Depending on the chemical composition, the pigment pigment for concrete has such characteristics as corrosion and temperature stability and color. Pigment composition has the following properties:

• Lightfastness - the dye retain the original, or a color close to it under the influence of ultraviolet radiation. The most resistant to this effect are natural pigments.
• Hiding power - the ability of pigmenting composition when applied to the surface to cover its color.
• Dispersion - depending on how finely the coloring pigment for concrete was grinded. The finer the grinding and the thinner the particles, the higher the coloring ability and the opacity of the composition.
• Chemical resistance to alkalis - stability of pigment color to the effect of alkaline media of cement mortar.
• Oil absorption, by which is meant the possibility of pigment particles to retain on the surface the required amount of a binder composition (oil). It depends on the origin and dispersion of pigments. The lower this indicator, the more durable and economical will be such a coating.

Methods of coloring

Today, there are two main ways of painting concrete structures. One of them is the coloring of the mortar of concrete during its mixing, and the second is the painting of ready-made structures from this material. Let us consider in more detail each of them.

Method of painting at the stage of mixing the solution

According to most experts, the most uniform coloring of the concrete structure is obtained when the dye, pigment for concrete, is introduced into the composition during mixing of the solution. Due to this, the concrete surface becomes uniformly colored throughout the entire thickness and does not lose its attractive appearance as the upper layer wears off. Color saturation directly depends on the amount introduced into the pigment solution, the price of which is quite high, which determines the higher cost of colored concrete in comparison with traditional ones. This method of staining is used for the monolithic pouring of various outdoor areas, the creation of decorative and retaining walls, the production of curbs, paving slabs and pavers.

To obtain a beautiful and "pure" color, it is best to use white cement and sand to prepare the mortar. To obtain the maximum effect, before introducing the pigment into the mixture, it is diluted in water to the consistency of sour cream, mixed thoroughly and left for several hours - to infuse. Then, stirring constantly, the resulting composition is poured into the solution and mixed thoroughly.

As already mentioned, today you can buy pigments not only in the form of dry mixtures, but also concentrated pastes, microcapsules and emulsions, which allows you to add pigment for concrete with your own hands and create a solution of the desired color and in the required quantity.

Staining of ready-made concrete products

For monolithic structures of concrete and finished concrete products, the most appropriate is precisely such a coloring technique. On the surface of already solidified structures, a layer of coloring composition is applied, penetrating into the structure of the material to be painted a few millimeters. How deeply penetrates the dye, directly depends on the carrier in which the pigment was dissolved.

In the role of a pigment carrier, various varnishes, colorless bases for facade paints and other water repellents can be used. The deeper the carrier can penetrate deep into the concrete structure, the longer it will retain color and attractiveness under the influence of ultraviolet and unfavorable environmental conditions.

Can I make pigment pigments my own?

Industrial dyes have a number of advantages over independently made, however, if desired and perseverance, the pigment for concrete with their own hands is quite feasible. To create such a dye you need:

• Water-soluble pigment for paints;
• Water-based primer for mineral surfaces;
• water.

If the primer is not concentrated, then 20 to 30% of water is added to the mixture. To obtain the colors closest to natural, natural, it is best to mix several pigments of the corresponding colors. It is important to remember that the so-painted mixtures after drying should be treated with lacquer as they do not have protective properties. To ensure resistance to moisture and sunlight, this treatment is carried out every 4-5 years.