Method of preserving plywood and particle board against decay and mould

A method of preserving plywood, particle board and similar wood composite products made from wood pieces/particles of a type normally susceptible to deterioration and decay from fungi and mold, and a binder used to adhere such wood pieces/particles together against rot and mold decay, comprising:

• (a) admixing a complexing agent used as a preservative of the wood pieces/particles, which is capable of binding transition group metals and preventing rot caused by fungi and mold, into the binder used in the manufacture of said wood composite products prior to the formation of said products;
• and
• (b) contacting said admixture of said complexing agent and said binder with said wood pieces/particles to provide adhesion therebetween, thus forming the wood composite product;
• wherein said complexing agent is present in an amount of 2 to 30 wt. % of the total admixture;
• and
• wherein the complexing agent used is ethylenediamine tetraacetic acid (EDTA), nitrilo triacetic acid (NTA), n-hydroxyethyl ehtylenediamine triacetic acid (HEDTA), diethylene triamine pentaacetic acid (DTPA), ethylenediamine-di-(o-hydroxyphenyl acetic acid) (EDDHDA), diethanol glycine (DEG) or ethanol glycine (EDG), or an alkali metal salt thereof;
• and
• wherein the binder is a phenolic resin adhesive or urea melamine resin adhesive.