Application of Grey Mica powder in inorganic non-expanded fire-retardant coatings

Fire-retardant coatings can be divided into two categories: expansion type and non-expansion type according to their fire resistance principle:

The main component of non-expanded fire-retardant coating is an inorganic thermal insulation material. It does not expand when exposed to fire and has good thermal insulation properties. It uses the inherent good thermal insulation properties of the coating and the heat absorption effect generated by ablation reactions such as evaporation and decomposition of some components at high temperatures to block and consume the transmission of fire heat to the substrate, thereby delaying the time when the steel member reaches the critical temperature. The coating thickness is generally 7 to 50 mm. Non-expanded fire-retardant coatings are generally non-combustible, non-toxic, resistant to aging, with reliable durability, and are suitable for permanent buildings.

2. After the expansion fire-retardant coating is formed, it is an ordinary paint film at room temperature. Under the action of flame or high temperature, the coating expands and carbonizes, forming a non-flammable spongy carbonaceous layer dozens of times or even hundreds of times thicker than the original thickness. It can block the heating of the substrate by external fire sources, thus acting as flame retardant.

The performance of Grimica powder in fireproof coatings:

1. Inert fragments of mica powder can also play the role of releasing the focus of stress in the paint film. This stress is caused by chemical reactions or by expansion and contraction of the paint film and painted surface, sliding between the mica sheets to eliminate additional force.

2. In fire-retardant coatings, mica powder tends to arrange parallel to the exposed surfaces of the paint film. Therefore, they form a layer of inert, solid and soft protective layer that is resistant to chemical corrosion and sunlight radiation.

3. Mica powder enhances the washability, adhesion, life of the paint film and corrosion resistance of the fire-resistant coating, improves the compactness of the coating, reduces the breathability of the coating, and prevents spots and cracks.

4. Mica powder sheet-like properties, heat resistance (600℃), electrical insulation and properties that are not susceptible to chemical erosion make mica powder a very suitable pigment blender.

5. Mica powder can block the precipitation of pigments in the paint, improve the suspension performance of fire-resistant coatings, and help mix the pigments evenly during construction.

6. It can replace some expensive paint pigments, such as aluminum powder, to reduce the paint cost. Different varieties of mica are transparent and have glitter colors such as gray and brown, making the coating beautiful. Some glitter paints are used.

Application suggestions:

Application of Grea GB series mica powder in inorganic non-expanded fire-retardant coatings

Addition: 10%-25%;

Typical features: high temperature resistance can be up to 600 degrees; inert high temperature resistance fillers, improve corrosion resistance of neutral salt spray, acid, alkali, oil and stains, etc.; improve the suspension performance of the paint; sheet-like structure, adjust the internal stress of the coating, improve the continuity, density and excellent mechanical properties of the paint film, improve the impact strength; improve the weather resistance of the paint film, make the paint surface color as new as new, and extend the service life of the substrate.