PRESERVATIVES (FUNGICIDES AND INSECTICIDES)
Fungicides
Copper naphthenate is the classic preservative and offers longlife protection at a relatively low cost. It is an extremely effective fungicide and insecticide and protects wood and textiles from destructive fungi, bacteria and termites. For use as a wood preservative, a copper naphthenate solution can be applied in the same way as a normal paint or woodstain. Copper naphthenate is also used as a fungicidal treatment to protect textiles. Cotton and canvas fabrics, from which awnings, tent walls and special sandbags are made, are vulnerable to destruction by fungi and micro-organisms if not treated with copper naphthenate.
The use of (TNTO) tributyl-tin-oxide has been discontinued in both timber preservatives and anti-fouling paints, but TBTN (tributyl-tin-naphthenate) is an approved alternative in some applications, especially in the treatment of dressed or graded timber.
Zinc naphthenate is used in the pharmaceutical industry in anti-fungal preparations.
Insecticides
Naphthenic acid is used as an emulsifier and a solvent improver in insecticides. Glycerin-phenolic-esters of naphthenic acids are used as direct insecticides.
Agricultural sprays made with sodium naphthenate are preferred to those made with sodium stearate, because the lower pH value of the aqueous solution of the naphthenate (8-9) is less damaging to plants than the higher pH value of the aqueous solution of the stearate (10 - 11). Alkaline earth metal naphthenates are used in fertilizers to prolong their storage life and increase the rate of spray.
Textiles Industry
Aluminium naphthenates are used in the textile industry to provide water and flame resistance.