Micaceous Iron Oxide (MIO)
Micaceous Iron Oxide (MIO) - Known as micaceous iron oxide SIMONO® MIO, this protective coating has been used around the world with great success for over one hundred years. Notable installations protected with this coating include the Eiffel Tower in Paris, the Sydney Harbor Bridge in Australia, and Big Ben in London. Although more commonly used in Europe, the finish is used in environments where long-term corrosion protection is critical, such as off-shore platforms, refineries, bridges, and electrical transmission towers. The benefits and performance attributes of this wet-applied finish make for an excellent specification feature.
SIMONO® MIO is a mined mineral with the chemical symbol Fe2O3, also known as hematite. It is a crystalline form of iron oxide that has a flaky, plate like structure similar to mica, hence its name. This inert material is insoluble in water, organic solvents, and alkalis; is un-reactive to most chemicals; and is heat stable up to its melting point of over 1000°C (2700°F). Micaceous iron oxide (SIMONO® MIO is non-toxic, non-oxidizing, non- corrosive, and nonflammable. As a result of these environmental characteristics, paint formulators world-wide have long considered this type of coating to be their primary choice in their arsenal of anti-corrosive protective finishes.
The plate-like structures or flakes of SIMONO® MIO align parallel to the surface when applied to the substrate, forming an armor-like layered shield similar to fish scales or roofing tiles. This alignment is key to providing enhanced barrier protection, ultraviolet light absorption, paint film reinforcement, and increased inter-coat adhesion. This tendency of the micaceous iron oxide particles to align parallel to the surface produces a barrier effect. The overlapping particles form a protective shield around the substrate that prevents the intrusion of moisture, organic solvents, and alkalis.
SIMONO® MIO is also impervious to UV radiation. This quality, combined with the layered structure of the material, protects the surface of the binder system in the coating from UV degradation and other weathering elements, giving this finish a service life of approximately twenty years. While this “built-in” protection ensures longevity of the paint surface for the long-term, other finishing techniques such as powder coating may exhibit signs of chalking or fading under extreme conditions of ultraviolet exposure that are commonly found in many regions.
The use of micaceous iron oxide additionally toughens and strengthens the coating, leading to greatly improved performance against blistering and increased substrate adhesion. The micro texture formed by the lamellar flakes creates a surface profile that allows for better adhesion between coats when the coating is dry.
Since the majority of SIMONO® MIO is iron oxide (over 90%), it has a coefficient of expansion similar to the metal substrate that it is protecting. This minimizes the possibility of cracking, flexing, or lifting of the paint from the surface, such as in extreme conditions of heat or cold.