Acetylation process

Step 1

It is the acetylated wood technology, that creates Accoya wood Over 80 years ago, the scientists around the world has studied the process.

The proven superior performance, delivered by the wood improvement method, has long been used as the “gold standard” against which other methods are measured.

Step 2

The chemical structure of any material will determine its physical properties. There is an abundance of chemical groups called “free hydroxyls” in wood, which absorb and release water according to changes in the climatic conditions to which the wood is exposed. This is the key reason why wood swells and shrinks.

It is also believed that enzymes’ digestion of wood initiates at the free hydroxyl sites – which is one of the principal reasons why wood is prone to decay.

Step 3

Acetylation effectively transfers free hydroxyls within the wood into acetyl groups. This is done by reacting the wood with acetic anhydride, which comes from acetic acid (vinegar when in dilute form).

The transformation from the free hydroxyl group to an acetyl group, greatly reduces the water absorption ability of the wood, and render the wood more dimensionally stable and extremely durable.

Step 4

Acetyl groups naturally exist in all wood species. This means that the acetylation process adds nothing into the wood, but alter the wood’s chemical structure to create an end product that is dramatically superior to its source species.

Accoya® wood, the end product, has no toxins in itself, moreover it releases none toxins to the environment.

Step 5

Accoya® wood is modified right through the cross section . Whereas, by contrast, virtually all other treatments merely insert chemicals (such as oils, ammonia or metal compounds) into the wood, to improve durability to a degree, but without dimensional stability.