Process for chemically hardening wood

A method of hardening wood, which comprises the steps of:

• a) applying onto a wood sample a cellular densification solution which contains a complex component of depolymerized lignin and is obtained by subjecting wood to a vapor phase pressure treatment with a pulping agent under heat and pressure conditions and for a period of time sufficient to allow vapors of said pulping agent to permeate the wood and cause a lignin depolymerization reaction, said pulping agent comprising the reaction product of a loweralkanolamine with a compound produced by electrolytic oxidation of the loweralkanolamine in an aqueous alkaline solution containing an acid addition salt of the loweralkanolamine;
• b) heat pressing the wood sample obtained in step (a) to cause said solution to vaporize and permeate the wood;
• and
• c) allowing the pressed wood to cool while maintaining same in a compressed state until cooled.