Wood additives generally have wood preservatives, wood waterproofing agent, wood mildew inhibitor, wood bleaching agent and wood flame retardants. The permeability of these auxiliaries is very strong and their solid performance is excellent after immersion in wood. And these additives are not easy to lose, strong durability, non-volatile and environmental-friendly. They are less corrosive to metals, do not affect wood painting and reduce wood insulation performance,  will not reduce the mechanical strength of wood.