BigPatents India

This invention relates to increasing the durability of the low cost and highly perishable timber like rubber wood for marine purposes. Through proper preservative treatment it is utilized for construction of small fishing canoes for inland and marine fishing. This will reduce the investment cost of the artisanal fishing craft. This is achieved through treatment of the wood with preservatives like copper chrome-arsenic (CCA) which is a water borne preservative and creosote which is an oil borne preservative. The preservative treatment increases the durability of wood, prevents attaack of the marine borers and does not affect the strength of the treated wood. The chemical treatment process was standardized to suit the requirement of the rubber wood for using it as a boat building material. This was achieved through an initial dip treatment of freshly felled planks in 2% CCA followed by stabilization of moisture content. Further treatment of scantlings is done in 7.5% CCA solution in a cement tank. The scntlings are seasoned until moisture reaches 25% and then treated with light creosote oil through immersion. The scantlings are assembled and canoe constructed.