1.The characteristics of blue change
Usually occurs only on the sapwood of the wood, and can occur in both coniferous and broadleaf wood.
Under the right conditions, blueing often occurs on the surface of sawn timber and the ends of logs. If the conditions are suitable, the blue-colored bacteria can penetrate from the wood surface to the inside of the wood, causing deep discoloration.
Light-colored wood is more susceptible to infestation by blue bacteria, such as rubberwood, red pine, masson pine, willow press, and maple.
The blue change does not affect the structure and strength of the wood, but the finished product made of the blue change wood has poor visual effects and is difficult to be accepted by customers.
Attentive customers may find that there are some changes in the color of some furniture, floors or plates in the home, which affect the overall beauty. What exactly is this? Why does wood change color?
Academically, we collectively call the discoloration of wood sapwood blue, also known as blue. In addition to blue, it also includes other color changes, such as black, pink, green, etc.
2.Incentives for Blue Change
After the trees are felled, they have not been treated in a timely and effective manner. Instead, the entire tree is placed directly on the wet soil, and it is exposed to wind and rain and microorganisms. 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 light blue.
Plain boards (white boards without anti-corrosion treatment and painting) are also left in a humid and airless environment for a long time, and they will also have blue symptoms.
The content of starch and monosaccharides in rubber wood is much higher than that of other woods, and it provides the energy required for the growth of blue bacteria. Therefore rubber wood is more prone to blueing than other woods.
3.The dangers of blue transformation
Blue wood is more perishable
Generally, wood is blued before it decays. Sometimes it is possible to see only the obvious decay defects formed during the later stages of the blue. It can also be said that discoloration is a precursor to decay.
Discoloration increases the permeability of wood
Due to the penetration of the blue-fungal mycelium, many small holes are formed, which increases the permeability of the wood. The hygroscopicity of the blued wood after drying is increased, and the decay fungus is easy to grow and reproduce after moisture absorption.
Reduce wood value
Due to the discoloration, the appearance of the wood is not good-looking. Users often refuse to accept this discolored wood or wood products, especially those used in decorative wood, furniture, and other areas where the appearance of wood is more important, or require price reduction. Commercially, preventing wood discoloration is an important aspect of maintaining the value of wood products.
4. Prevention of blue discoloration
After logging, 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 below 20%.
Treat wood with anti-tarnish agents in a timely manner.
Post time: Jan-09-2020