Today, bakelite varnishes are a popular substance used in construction. They are made by evaporating phenol and formaldehyde. Moreover, for this it is necessary to make a special alcohol-based resin solution. So that the main components react with each other, ammonia is added. This component gives the finished product a certain smell.
Main characteristics
Bakelite varnishes are toxic since phenol and formaldehyde vapors are released during the manufacturing process. There are acceptable limits for the presence of a given substance within a manufacturing facility. A concentration of 0.3 mg / m³ is not hazardous to humans. Higher rates lead to poisoning, and in some cases, to death.
Bakelite varnish, the composition of which includes flammable substances, has a flash point of 15 º. Complete ignition occurs at a temperature above the previous indicator. Fire safety bakelite varnishes belong to class A. Basic information about the properties of this substance is described in the regulatory documentation, namely in GOST 12.1.044. If a fire occurs in the production hall, water, sand, as well as a special type of chemical and mechanical foam, are used to localize it.
Bakelite varnish: application
These substances are used in various industries. The main purpose is to protect surfaces and parts from moisture or other aggressive substances. They are also used for painting gas tanks. Bakelite varnishes are superior to other types of such products in their functionality, as they are used to impregnate and glue individual parts of the part.
Most often, plywood is treated with such compounds . Bakelite varnish, the technical characteristics of which are described in the article, are used not only in construction, but also in other types of industry. Among them are the following:
- shipbuilding - manufacturing decks of ships and yachts;
- automotive industry - the production of the bottom coating, as well as individual components;
- construction - flooring, exterior decoration of buildings, roofs, decoration of rooms and furniture;
- for the production of firearms and sports facilities;
- for the manufacture of children's goods and much more.
The process of obtaining varnish
To make such a composition, it is necessary to use the following substances: phenol, ethyl alcohol, formalin and ammonia. What characteristics of bakelite varnish are known to us? They depend on the characteristics of the constituent substances.
Characteristics of constituent materials
So, the first substance is phenol. It is an organic compound that dissolves upon interaction with water. Its freezing temperature is 40º. Formalin is a dangerous toxic substance that is considered poison. It is a clear liquid having a low level of reactivity. Ammonia is not used in its pure form, but a weak aqueous solution is made of it.
Ethyl alcohol is used for pumping carbon-containing substances. The end result is a clear liquid. It can be painted in various colors. Also, the composition of the varnish includes vegetable oil and cellulose. Before adding it, it undergoes a thorough treatment.
Main types
Today, there are 9 main types of bakelite varnishes. Each of them is used in a specific industry. In addition, they have different percentages of constituents, that is, phenol, formaldehyde, ethanol and ammonia. With a change in the quantity of one of the indicators, the properties of the varnish and its function change. For example, you can compare these brands of varnishes:
- SBS-1 - for processing plastic and plywood, which is used in the external and internal decoration of the house.
- LBS-4 - for various plastics containing mineral fillers.
- LBS-1 and LBS-2 - are considered Bakelite varnishes of the highest grade and are used for coating plastics and fiberglass products.
Varnish is applied to the surface of building materials or parts with a brush or roller. In the end, a special film is formed on the surface, consisting of organic or inorganic elements. It protects the surface from moisture and other aggressive substances.
Repair Use
This type of varnish is used both for internal and external works. Using a special dye, you can achieve the desired color of the product. In this case, the properties of the varnish will remain unchanged. However, its use at home is complicated. Before applying, it is necessary to clean the surface of excess debris and dry it. After varnishing, the surface must be heat treated. In this case, the temperature should reach 160º. To achieve it will have to work hard.
Natural drying of the surface is carried out for 4 hours. For more thorough protection, a second layer is applied on top, which contains a special filler. All subsequent ones go without filler. Ultimately, the film thickness reaches 0.5 mm.
To increase the mechanical strength on the surface, a cotton fabric is applied, which is impregnated with bakelite varnish. It is stacked in about 3 layers. This technology is as follows: to begin with, the fabric must be thoroughly washed and dried to get rid of starch.
It is cut into small pieces and immersed in a container with varnish. It should be soaked for 5 minutes. Next, the fabric is taken out of the container and squeezed with rubber gloves. The impregnated pieces are taken out into the open air and dried so that the presence of solvent is minimized. Primed and dried cloth is applied to the surface and varnish is applied from above with a brush. If there is a need to increase the mechanical strength of the pipes, then the fabric is cut into strips of small width. Then the procedure follows the same pattern.
Ultimately, a film forms on the building surface, which will protect the material from moisture and other factors. It can be damaged under several conditions:
- if the surface will be affected by temperatures above 20 º for a long time;
- if the surface covered with varnish, direct sunlight.
Despite the fact that repair with bakelite varnish causes some difficulties, judging by the reviews of consumers, this material remains quite in demand.
Price policy
The cost of the composition is quite diverse and depends on the brand, as well as the place of application. The price of such compounds is in the range from 300 to 1000 rubles per liter.
Conclusion
According to the masters, bakelite varnish is a popular substance that is used not only in industry, but also in everyday life. It is used for the manufacture of various chemicals and materials. The people who used it claim that the technology for applying it is quite simple. Only they specifically note that when working with varnish, certain rules should be followed. First of all, the room to be painted should be well ventilated. You can not stay in it for a long time, since the condensing vapors of phenol lead to poisoning.
So, we found out what this composition is, and also found out what are the characteristics of bakelite varnish.