The containers in which food is stored should be protected from rapid spoilage and corrosion. There are enamels that are safe for humans and suitable for use in the food industry. One of them is KO-42 paint, which is not harmful to people and animals.
- Material Description
- Fields of application
- Differences of KO-42 from KO-42T
- Technical specifications
- Preparation for application
- Paint Instruction
- Packing, transportation, storage
- Security measures
Material Description
Enamel KO-42 is an environmentally friendly paint and varnish material with anti-corrosion properties. Enamel is widely used where surface protection against water and rust is required, while the products come in contact with food. The material is produced in containers weighing 1, 15, 50 kg, the cost per 1 kilogram is about 300 rubles. A subtype of KO-42T material is also produced, having the same technical characteristics and similar applications.
The composition of the two-component material is zinc powder with ethyl silicate binder components, with copolymers of vinyl chloride, vinyl acetate, plasticizers. Paint color - matte gray. The material is waterproof, withstands high humidity or being in water, does not emit harmful substances in liquids. The product can withstand short-term temperature drops of –60 ... + 300 degrees, it is possible to apply paint even at a negative temperature (up to –30 degrees).
to contents ↑Fields of application
The instructions indicate the description and application of the materials. KO-42, KO-42T give a corrosion-resistant coating that is harmless to humans, so the material is used for such purposes:
- protection of reservoirs, tanks, barrels for storing drinking water;
- drawing on a container for storage and transportation of products, food liquids and raw materials.
The use of the material by cold galvanizing also allows you to use it to protect maritime transport, ships under construction for river navigation. This method helps prevent contact with the base metal even at high temperatures. This allows you to prevent the release of chemical impurities to the outside.
Differences of KO-42 from KO-42T
The main difference is in heat resistance. Enamel KO-42T withstands temperatures up to +100 degrees, therefore it is most often used for painting pipes of hot drinking water supply. Enamel KO-42 is usually used where contact with cold or warm water is supposed.
Technical specifications
According to the available certificates of conformity, both of these materials must have the following technical characteristics:
- coating - gray, matte, without impurities, smooth, smooth;
- viscosity according to the VZ-4 viscometer at a temperature of +20 degrees - 18–32 s;
- fraction of solids - 68–72%;
- drying time to degree 3 at +20 degrees - 20 minutes;
- film adhesion - 1 point;
- bending elasticity - 3 mm;
- impact strength according to the U-1 device - 50 cm;
- resistance to direct action of water at +20 degrees - 96 hours;
- consumption per layer - 250-330 g / sq. m;
- layer thickness - 30–40 microns;
- number of layers - 4.
Ethanol in the amount of 5% by weight of the paint is used as a solvent. Subject to the conditions for the application and implementation of four layers, the coating will last at least 3 years. After combining the powder with the base, the viability of the paint will be 6 hours at room temperature.
Preparation for application
Metal surfaces are cleaned from old coatings, rust, dirt, oil with sandpaper or sandblasted. If required, after the surface is degreased with toluene, xylene. This should be done before staining, waiting no more than 6 hours.
Material also needs to be prepared. To do this, 1 part of the base is combined with zinc powder (2 parts), slowly, in portions, interfering with the latter. The paint is mixed well until it becomes uniform in texture. Then you should wait half an hour until the air bubbles disappear. To bring the material to the desired viscosity, alcohol is added; in its absence, acetone can be used. The amount of acetone, like alcohol, is up to 5%.
The method of pneumatic spraying can be used for application; for it, the working viscosity will be 17–25 s. You can also use a brush and a roller, then the viscosity should be 25–35 s.
Paint Instruction
Staining is done only if the surface is completely dry. Air temperature during operation + 15 ... + 40 degrees, humidity - up to 80%. When using pneumatic spraying, the distance between the nozzle of the apparatus and the base is 10–20 cm, and the air pressure is 1.5–2.5 kgf / sq. cm, nozzle size in diameter - 1.8–2.5 mm. The brush is usually used only for painting hard-to-reach spots, ends, edges, seams.
The base is painted on 3-4 cross layers, intermediate drying is 20-30 minutes at room temperature. If the temperature is negative, the drying time is extended by 2-3 times. Final polymerization and the appearance of full protective properties are achieved after 7 days. Only after the indicated time can the products be put into operation.
to contents ↑Packing, transportation, storage
GOST 9980-3 applies to packaging rules, labeling - GOST 9980-4. The product belongs to the third hazard class, it is transported in special containers with the appropriate labeling. All types of transport are used - water, air, rail, automobile. Shelf life of paint - 1 year from the date of issue. The paint is stored in a tightly closed container, protected from moisture, the sun at a temperature of –50 ... + 40 degrees.
to contents ↑
Security measures
The presence of solvents causes fire hazard and toxicity of the paint when working with it. The area around the work site should be well ventilated. Workers protect their respiratory organs with respirators, hands with gloves or special pastes. In enclosed spaces, before painting products, a gas mask should be worn. In order to avoid fire, it is necessary to exclude smoking, sparks in the material. In the room must be a fire extinguishing agent - sand, fire extinguishers.
