Technology of bamboo production

The bamboo stems are marked early for the right harvest time, 
Photo: Guillaume Bonnefont by Moso International B.V.

Harvesting the right bamboo

Endless bamboo forests grow in the mountains to the east of China. The bamboo stems must not be too old to be processed into the high-quality MOSO bamboo products; ideally they are harvested when they are five years old. Younger stems are not yet completely woody, while older ones turn grey and brittle. The very best raw material is the prerequisite for the very best end product. The quality of the bamboo stems can be partly assessed at the time of purchase, but is difficult to recognise in the new end product. However, the quality of the bamboo raw material can still - unexpectedly - come to light later.

Sorting of the split lamellas
Photo: Guillaume Bonnefont by Moso International B.V.

Manufacture of bamboo strips from hollow tubes

The freshly harvested bamboo stems are split lengthwise into strips. This step of the production process goes beyond the mere splitting of the hollow bamboo tube. The inner and outer bark must also be removed so that the surface is optimally prepared for gluing. The higher the quality of the bamboo strips, the more waste is produced, as more bamboo has to be peeled off the slats to ensure that there is really no bark left. You can judge the quality of the strips when you buy them, but you won't see the difference in the end product at first glance. MOSO only accepts the very best strips for its bamboo products.

Splitting of the lamellas into fine strips
Photo: Guillaume Bonnefont by Moso International B.V.

Crushing of the slats for further bamboo production

The bamboo strips are then cut into millimetre-thin strips and prepared for further processing. The quality of this step plays a decisive role for the quality of the binder impregnation and gluing in the next production steps. If the strips are to be better refined, this requires more precise handling and thus higher costs.

After the thermal treatment the colour of the bamboo product changes. 
Photo: Guillaume Bonnefont by Moso International B.V.

Thermal treatment for adjustment of stability and colour

Most bamboo products are available in three standard colours: natural, caramel and chocolate. Natural colour is the natural material colour, without any treatment. When the bamboo strips are steamed, they turn brown: caramel. And after a thermal treatment at approx. 200 °C their colour changes to a dark brown: Chocolate. This treatment also changes the material: the sugar component of the bamboo is broken down, making the material more durable and stable. This treatment can be carried out at different temperatures and for different periods of time. Some manufacturers prefer lower temperatures and shorter treatment times due to lower costs. MOSO always focuses on the optimal durability and stability of the final bamboo product.

Dynea produces high quality resins

Bamboo products contain bamboo and binders

The finely cut bamboo strips are impregnated with a binding agent to connect the bamboo strips and are highly compacted. MOSO aims to replace the chemical resins with biological binders. However, because the quality of the end products has the highest priority for MOSO, this is not yet possible. To this day, no bio-binder can meet the high requirements for the manufacture of top-class products. Until such time as organic binders can be used in production without impairing quality, binders of well-known brands will be used. This ensures that emissions are kept to a minimum.

It is very difficult to determine the type and quantity of binder used once the end product has been manufactured. Nevertheless, this is one of the most important differences between density and strand woven bamboo products. Binder costs have a significant impact on total production costs. For cost reasons, many plants produce with their own binders or use binders from local manufacturers, while MOSO consciously chooses to process well-known branded products such as Dynea.

Compaction of the bamboo material

There are various methods for compressing bamboo

Depending on the type of product, the dimensions and the required bamboo colour, compression (compaction) can be carried out using cold or hot pressing systems. Each binder needs a certain temperature for hardening during compression. In addition, the way in which the fine bamboo strips are inserted into the moulds influences both the stability and the appearance of the final product. After this important production step, the material is first tested by trained MOSO quality inspectors to ensure the quality of the final product. By the way, it is practically impossible to test this without laboratory testing.

Quality control by MOSO inspectors

The moisture content defines the stability of bamboo products

Like all other natural materials, bamboo is sensitive to moisture: it swells with increasing moisture content and shrinks with decreasing moisture content. It is crucial that the moisture content is reduced and controlled in all production steps in drying chambers. The moisture content of the final product supplied by the manufacturing plant has a decisive influence on the technical behaviour of the bamboo products after installation. A higher moisture content of the product usually leads to more problems with moisture fluctuations later on.

Since strand woven or density bamboo products are extremely dense and hard, it is difficult to determine the moisture content of the final product. Only through our continuous product development over the last 10 years has MOSO been able to define the method for controlling the moisture content of each end product. To ensure the high quality of bamboo products in their final application, local MOSO quality inspectors monitor the moisture content of each production batch during and after production.

Final density production

Final Density Bamboo Product

The final step in the production of density bamboo is the final profiling of the material. A material as hard and dense as Density Bamboo places the highest demands on the tools used for profiling. MOSO guarantees the correct processing of the material into end products by using high-quality plant technology, often from European manufacturers. A good example of this is the way in which the profiles for click systems are cut into the material. The best machines also enable the best finishing of the surfaces. Depending on the product, MOSO uses Density Bamboo as a top layer for panels and floor coverings or as solid beams or floor coverings.