On the Practical Use of Micro-emulsified Metal Naphthenate.(1) The efficacy of the metal naphthenates as the wood preservatives in pressure treatment

• Published in: MOKUZAI HOZON (Wood Protection) Vol. 15; no. 6; pp. 261 - 272
• Main Authors: TAKEUCHI, Takatsune, MATSUSAKA, Hiroshi, KOBAYASHI, Tomonori, AKAO, Shinichi, HIGAKI, Miyato
• Format: Journal Article
• Language: English
• Published: JAPAN WOOD PRESERVING ASSOCIATION 25.11.1989
• ISSN: 0287-9255; 1884-0116
• DOI: 10.5990/jwpa.15.261

Copper naphthenate and zinc naphthenate are wood preservatives which have been used with organic solvent for a long time. The authors examined the efficacy of the micro-emulsified metal naphthenates as the wood preservatives in pressure-treatment according to JWPA and JIS standards. The results were summerized as follows. 1. The efficacy of wood preservatives against decay and termite attack, the amounts of iron corrosion and hygroscopicity of preservatives and field test results for 2 years adapted to the requirement of JWPA or JIS standards under tested concentration. 2. The average amount of preservatives absorbed were 209-460 kg/m3 with TOYOSOL CU and 116-336 kg/m3 with TOYOSOL ZN by pressured application which were indicated a good preserving performance against decay and termite attack. In surface layer (1 cm in the groundsill depth) the penetration of preservatives was showed 100%. These groundsills were found to be the same permiable degree as CCA treated groundsills. 3. The emulsion of these preservatives showed good stalling without being a affected by iron ion or wood sawdust. 4. The contents of the active ingredient in the treated wood and the emulsified preservatives were easily assayed by atomic absorption spectroscopy. Also, penetration of the preservatives into groundsills was easily detected by coloring with 0.1% dithizon-trichloroethylene solution. In conclusion, TOYOZOL CU and TOYOZOL ZN were shown to be good preservatives for pactical use.