PURPOSE: To manufacture a modified timber of superior flame-retardant properties, corrosionproof and mothproof properties, dimension stability and the like by applying alkali treatment to the timber simultaneously and/or before impregnation when a raw material timber is impregnated with one of the combination of cation containing treatment liquid and anion containing treatment liquid for generating non-soluble and incombustible inorganic material by mixing, and then impregnating the timber with the other liquid.
CONSTITUTION: In order to form a non-soluble and incombustible inorganic material in the timber organization, aqueous solution prepared with a group of inorganic compounds constituting a cation solution of the non-soluble and incombustible inorganic material, which forms cation containing treatment liquid, and water solution prepared with another group of inorganic materials constituting an anion portion, which forms anion containing treatment liquid, are infiltrated into the timber organization successively for impregnation. Simultaneously the first treatment liquid is infiltrated, and alkali treatment is also carried out. Alternatively, before infiltrating the first treatment liquid, alkali treatment is carried out.
YUSA YUKIHIKO
ONISHI KENJI
