A method for liquid treatment of a wood species
AssigneeSuperwood A/S
InventorsBenny Petersen, Finn Imsgard, Anders Westh Kjellow, João Luis Beja Fernandes
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Abstract
The present invention relates to an improved method for impregnating a porous material, such as wood, more specifically a method in which an active ingredient to be deposited within the porous material is dissolved in condensed carbon dioxide and impregnated in the material
Claims11
A method for treating a porous material with an active ingredient comprising the steps of
- a. providing the porous material to a container;
- b. applying pressure, in the container, by providing gaseous carbon dioxide to the container, said container comprising the porous material, at a temperature below the critical point of carbon dioxide;
- c. applying further pressure to the container to provide condensed carbon dioxide;
- d. providing an active ingredient, optionally solubilized, to the container, optionally premixed with carbon dioxide;
- e. maintaining the pressure obtained in step c. for a predetermined period of time;
- f. increasing the temperature in the container to a temperature above the critical point of carbon dioxide at the prevailing pressure to provide carbon dioxide in supercritical form;
- g. maintaining the conditions obtained in step f. for a predetermined period of time;
- and
- h. reducing the pressure to atmospheric to provide a treated porous material and carbon dioxide in gaseous form.
A method according to any of the preceding claims wherein the active ingredient is selected from the group consisting of polymers for increasing water resistance, modifiers of the building blocks of the porous material, organic and inorganic biocides, aromas, colorants and organic or inorganic salts.
Method according to any one of the preceding claims, wherein the treatment is selected among impregnation, extraction, dying, improving water resistance or drying and any combination thereof.
Dependencies are inferred from the claim text.