The coating of fireproof material is mainly used for the fire safety of buildings, Fire-retardant coating on the base material, in addition to play the role of decoration, corrosion and other functions, the main role is to encounter or heat radiation, the coating will quickly occur physical and chemical changes and barrier heat, prevent the spread, play a flame retardant role. Or when it encounters fire, it can insulate heat and reduce the surface temperature of the subbase to play a fire-resistant role.
There are many types of fire-retardant coatings, generally according to the different classification of grassroots, there are:
- steel structure fire-retardant coating
- concrete fire-resistant coating
- wood fire-resistant coatings
Based on the composition and the mechanism of fire retardant coating, fire retardant coatings can be divided into:
- Intumescent fire resistant coatings
Intumescent fire retardant coating is a widely used fire retardant coatings, its characteristics are: in or under the action of high temperature, can produce dozens of times thick than the original coating even hundreds of times the non-combustible spongy carbon layer, The utility model can effectively prevent the action of external heat source, and at the same time produce non-combustion gases, such as CO2, NH3, HCl, Br2 and water vapor, and reduce the concentration of combustible gas at the bottom and oxygen concentration in the air, so as to play the role of fire prevention and flame retardant.
- Non-intumescence fire resistant coatings
Non-intumescent fire retardant coating is in the fire when the coating does not change, and the formation of a glaze protective layer, isolated from the role of oxygen, to avoid combustion reaction. Its effect of fireproof and heat insulation is inferior to intumescent fireproof coating. According to the actual application of fire retardant coatings and ultra-thin (indoor and outdoor), thin coating (outdoor and indoor) type, thick coating (indoors and outdoors) type fire retardant coating:
- Ultra-thin: dry film thickness of 3mm or less, generally used for coating the need for good adhesion, corrosion, weather resistance as one of the outdoor steel structure and building fire protection coating. Fire-resistant limit ≤ 2h, mostly for solvent-based foaming decorative fire type coating, the company’s fire retardant coating belongs to this.
- Thin coating type: dry film thickness between 3-7mm, mostly used for anti-corrosion and weatherproof steel structure and building wall fire coating, Requirements of better adhesion and water resistance, fire resistance limit ≤ 2h, this fire retardant coating is divided into waterborne intumescent fire retardant paint and solvent intumescence fire resistant paint two categories. The former has the characteristics of environmental protection, low toxicity and dry at room temperature, but the moisture-proof is poor. When the environment is damp, the paint is easy to fall off and is suitable for dry places. The latter moisture resistance, adhesion is obviously superior, but the solvent volatile odor, not conducive to environmental protection, the company can supply one of the above two according to user requirements.
- Thick coating type: dry coating thickness between 7-45mm, generally used for building firewalls, floors and steel structures or for thermal insulation high temperature compound layer in buildings, The fire resistance limit of 0.5 to 3 h, the thick coating of the fire retardant coating is mostly inorganic waterborne non-expansion type, in this thick coating fire resistant coating, There is also a fire insulation coating, in addition to the fire function, but also has a thermal insulation performance, thick coating coating is also characterized by thick coating, coating density is smaller, thermal conductivity coefficient is also very small, the overall heat transfer effect is low.