Fire-retardant coatings are made to improve the fire resistance of materials, slow the flame spread speed of the material, by spraying the paint on the surface of those flammable materials, or to prevent combustion in a certain period of time. This type of coating is called fire retardant coating, or flame retardant coating.
Principle of fire protection
The fire protection principle of fireproof coatings can be roughly summarized into the following five points:
(1) The fireproof coating itself is flame retardant or non-flammable, so that the protected substrate does not directly contact with the air, delaying the ignition of the object and reducing the burning speed.
(2) In addition to its inherent flame retardancy or non-combustibility, fireproof coatings also have a lower thermal conductivity, which can delay the transfer of flame temperature to the substrate being protected.
(3) The fireproof coating is decomposed into a non-combustible inert gas by heat, which dilutes the combustible gas decomposed by the protected object, so that it is not easy to burn or the burning speed is slowed down.
(4) The nitrogen-containing fireproof coating is decomposed by heat to form groups such as NO and NH3, and combines with organic radicals to interrupt the chain reaction and lower the temperature.
(5) The intumescent fireproof coating is thermally expanded and foamed to form a carbon foam insulation layer to seal the protected object, delay the transfer of heat and the substrate, and prevent the object from burning or causing a decrease in strength due to an increase in temperature.