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Copper Naphthenate

Tenino and Cu-Nap Concentrate

Copper Care Wood Preservatives, Inc. can help you get the copper naphthenate you need. Cu-Nap Concentrate and ready-to-use Tenino Copper Naphthenate are available in a wide variety of packaging options: two-hundred and seventy gallon totes down to pint bottles. Pints of Tenino for utility linemen. Quart containers of ready-to-use Tenino stocked by retailers and 55 Gallon drums of Cu-Nap Concentrate for post treaters - Copper Care has Tenino and CuNap Concentrate in packaging that works for you.

Tenino Copper Naphthenate Meets The Standard for Field Treatment of Wood - Section 7 of AWPA Standard M-4 from 2015 describes preservation systems for field treatment of wood:

The appropriateness of the preservation system for field treatment shall be determined by the type of preservative originally used to protect the product and the availability of a field treatment preservative. Because many preservative products are not packaged and labeled for use by the general public, a system different from the original treatment may need to be utilized for field treatment. Users shall carefully read and follow the instructions and precautions listed on the product label when using these materials.
Copper Naphthenate preservatives containing a minimum of 2.0% copper metal are recommended for material originally treated with copper naphthenate, pentachlorophenol, creosote, creosote solution or waterborne preservatives.

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Copper Care Wood Preservatives' Cu-Nap Concentrate (8% Cu as metal) is a liquid Copper Naphthenate wood preservative that can be diluted with diesel or mineral spirits. It is widely used as a dip treatment for fence posts using a 24-hour soak. Cu-Nap Concentrate is labeled for the treatment of posts, poles, lumber, siding, boxes, roof shakes and shingles, fence pickets, landscape timbers, cellulose textiles and cordage. Apply by brush, dip, or pressure treatment. Cu-Nap Concentrate is a cost effective solution for large volume, commercial users. For dilution and other detailed information, refer to the product label, the product flyer, or call us.

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Broad Use and Safer Handling

Copper Naphthenate provides protection against wood decay and the superior water repellent qualities of an oil borne wood preservative. Copper Naphthenate treatments result in wood that is cleaner to the touch, with minimal excess preservative coming in contact with the environment. Copper Naphthenate is the green choice in preservatives because it is not a restricted use pesticide. With durability equal to or better than other preservatives, it is a great choice for bridge timbers, barn timbers, glulam beams, salt storage domes, protector boards and highway railings. For many applications copper naphthenate is the best wood preservative available to contractors and builders. Use copper naphthenate when wood will be in contact with the ground and as an end cut treatment when applied to cut pressure treated wood.

Packaging That Lasts

Our Black Nylon fortified HDPE one-gallon jugs and our clear PET pints and quarts provide excellent resistance to aromatic hydrocarbon degradation. Our containers and copper naphthenate products have a shelf life rating of five years. Our unique induction seal uses 18 microns of copper foil which eliminates galvanic degradation of the seal. Trust Copper Care Wood Preservatives to provide the best packaging solutions for Cu-Nap Concentrate and Tenino Copper Naphthenate.

Formosa Subterranean Termite Protection

University of Hawaii in studies demonstrates Copper Naphthenate can provide effective protection against Formosan Termites. To achieve effective, long-term protection against termites, treat to the required AWPA Use Category 4C requirements.

Reveals Natural Wood Grain

The bright green color of wood freshly treated with copper naphthenate will become brown in outdoor exposure. Multiple studies demonstrate no excessive corrosion of hardware and fasteners due to contact with the preservative.


USDA Forest Service Forest Products Laboratory studies document long-term performance. American Wood Protection Association (AWPA) Standards ensure peer review and qualify intended applications.

Peeled posted treated with Copper Care Wood Preservatives Cu-Nap concentrate copper naphthenate

After brief exposure to elements wood treated with copper naphthenates develops a natural copper tone.

General Use Pesticide

Copper Naphthenate is an oil-borne wood preservative classified as general use by the United States Environmental Protection Agency (EPA) under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). Copper Care Wood Preservative’s Tenino, and Cu-Nap concentrate products are EPA-registered “general use” preservatives and have been standardized for use by the American Wood Protection Association (AWPA). Creosote and pentachlorophenol are used in pressure treatment for utility poles, bridge timbers and railroad crossties. Copper naphthenate is the only non-restricted use product in this market. Copper naphthenate has a low mammalian toxicity profile.

Time Tested

Copper Naphthenate has been used as a wood preservative for over one hundred years with many applications for use, including field boxes, benches, flats, fence posts, water tanks, canvas, burlap, ropes, nets, greenhouses, utility poles, crossarms, and wooden structures in ground contact and above ground contact.

Waste Disposal

Copper Naphthenate treated wood waste is neither a listed nor a characteristic hazardous waste according to the current EPA regulations under the Resources Conservation and Recovery Act (RCRA). It may be disposed of in landfills in accordance with federal, state and local regulations.

100% Domestic

The primary constituents of the treating solution are derived and/or manufactured from domestic sources by US owned companies.