1, the characteristics of blue change
It usually only occurs on the sapwood of wood, and blue light can occur in both softwood and hardwood.
Under suitable conditions, blue is more likely to occur on the surface of the sawn timber and at the ends of the logs. If the conditions are appropriate, the blue bacteria can penetrate from the surface of the wood into the interior of the wood, resulting in deep discoloration.
Light-colored wood is more susceptible to blue-stained bacteria, such as rubber wood, red pine, masson pine, willow, maple and so on.
Blue change does not affect the structure and strength of the wood, but the finished product made of blue-variable wood has poor visual effects and is difficult to be accepted by customers.
2, the cause of blue change
After the trees are cut down, they are not treated in a timely and effective manner. Instead, the whole tree material is placed directly on the wet mud land, and it is exposed to wind, rain and microbes. When the moisture content of the wood is higher than 20%, the internal environment of the wood can be chemically changed, and the wood appears pale blue.
Plain boards (white blanks that have not been treated with anti-corrosion treatment and painted) have been left in a humid, non-ventilated environment for a long time, and blue symptoms may also occur.
The starch and monosaccharide content of rubber wood is much higher than other woods, providing the energy needed for the growth of blue bacteria. Therefore, rubber wood is more prone to blue color than other woods.
3. Prevention of blue change
After felling, the logs should be processed as soon as possible, the sooner the better.
The processed wood should be dried as soon as possible to reduce the moisture content of the wood to less than 20%.
Timely treatment of wood with anti-tarnishing agents