Study of Insect Proof Plywood by Mixing Chlordane with the Glue

Abstract

Methods of manufacturing insect proof plywood was investigated by mixing the insecticide with glue. Chlordane was selected as the insecticide because of its standardized quality, availability of quantitative analysis and relatively low mammalian toxicity. From the result of quantitative analysis, it was demonstrated that plywood with urea resin glue was the highest for the retention of chlordane, followed by those with melamine and phenol resins. Bio-assay for insecticidae effect was made in surface, sub-surface, glue-line and center of each plywood, using adult of Tribolium castaneum MEREST as the substitute organism for Lyctus-beetle. The effect was higher in melamine-glued plywood than urea- and phenol-glued ones. Effective does of chlordane in each layer of the plywood, although a slight difference was found depending upon the type of resin used, was 600 g/m^3 on the glue-line, 800 g/m^3 on the center face and 1000 g/m^3 on the sub-surface. For a long residual effect, 900 to 1000 g/m^3 was required for glue-line mixture.