When used in an intumescent coating, glassflake offers increased environmental stability, allowing the intumescent to perform as closely as possible to the freshly applied coating as possible. The barrier properties of glassflake reduce initial water absorption in situ and over time, prevent the leaching of crucial small molecules, such as boric acid, vital for the intumescing reaction. Given the often harsh environments where fire protection of steel is required against hydrocarbon type fires, such as in the oil and gas extraction market, the additional benefits of glassflake are evident in corrosion protection and weather stability of the coating system.
Glassflake is used to improve the fire performance of a range of materials, in offering both fire retardancy as well as improvements to intumescent insulation coatings. Fire retardancy is offered by the multi-layer barrier that glassflake provides, this prevents the permeation of oxygen through a polymeric material and preventing onward spread of the fire. Where the organic content does burn the remaining glassflake provides reinforcement to the char structure, allowing to act as further insulation. This effect acts a physical retarder, often used in conjunction with a chemical fire retarder to quench fire.