Wood is good, but ...

Wood is a beautiful material. It is strong in relation to it's weight, it is durable, renewable and it is available in a myriad of colors and textures. Natural wood also has a number of disadvantages. It is vulnerable to attack by fungi, insects and other organisms, it swells and shrinks and if left in outdoor conditions it turns grey rapidly. Most of these disadvantages can be overcome if the molecular structure of the wood is slightly changed. Technologies that aim to do this are known under the name: wood modification.

Wood Modification

Ideas on wood modification can be found back in literature of more than 70 years ago. However, these technologies were emerging on the market for the first time in the 1990's. The reasons for this are simple. First, for many years, excellent tropical hardwood species were available at very low prices and second in order to give lesser durable wood species a longer service life, cheap wood preservation methods were available. The latter are based on toxicity of biocides that are impregnated into the wood. Wood modification is not based on toxicity. It changes the molecular structure of lignin, hemi-cellulose and cellulose, which are the main constituents of wood. Because of these changes the material looses it's affinity with water, which leads to a dimensionally stable and fungal resistant material. The stability prevents micro-checking and other physical degradation processes.

chemical modification of wood

Natural wood with hydroxyl groups (brown spheres) holds water (blue spheres). In modified wood the hydroxyl groups are replaced by hydrophobic groups (green spheres).

UV stability

All natural wood becomes grey in normal weathering conditions. This is an extremely complicated process or rather a combination of several simultaneous processes. Lignin can oxide under the influence of UV-light. The oxidation products are water soluble and will therefore leach out of the wood with rain, leaving behind a whitish fibrous surface. At the same time the wood is occupied by discoloring fungi that have dark hyphae. The combination of white and black renders a grey surface. EPHOKAM uses a unique and protected second generation wood modification technique. It stops the UV initiated oxidation of the lignin and it makes the wood incompatible with the digestion system of wood eating fungi at the same time. This is the secret behind the second part of our motto: "… quality that stays"!