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Treated Wood Tempest

Industry is aghast as Viance and Osmose swap charges over preservative formulas

by Marc S. Reisch
April 13, 2009 | A version of this story appeared in Volume 87, Issue 15

Credit: Viance
Viance alleges MCQ-treated wood, such as this sample, fails prematurely.
Credit: Viance
Viance alleges MCQ-treated wood, such as this sample, fails prematurely.

COMPETITORS IN THE chemical industry don’t often openly criticize one another’s products. But an ongoing tiff between two of the four largest U.S. makers of preservatives for pressure-treated wood, Viance and Osmose, has generated charges by Viance, countercharges by Osmose, and a federal lawsuit.

A group of pressure treaters—whose equipment forces preservatives deep into wood beams and decking material to prevent rot, mold, and insect attack—has become involved too. Fearing damage to the industry’s reputation as the spring deck-building season gets under way, the treaters have asked Viance to back off efforts to discredit Osmose’s preservatives. “We’re a good industry with good products,” says Harold I. Bumby, president of Maine Wood Treaters, one of the firms asking Viance to abandon its attack. “We shouldn’t be trashing one another.”

In the lawsuit, filed last month in U.S. District Court for the Northern District of Georgia, Osmose charges that Viance “has engaged in a pattern of activity” since spring 2008 to discredit micronized copper quaternary compound (MCQ) wood preservatives made by Osmose “in a false and malicious media campaign.” Viance makes a competing wood preservative, alkaline copper quaternary compound (ACQ). Osmose asked the court to “put a stop to the defendant’s actions” and award it unspecified monetary damages. Viance, a joint venture between Rockwood Holdings and the Rohm and Haas division of Dow Chemical, said it has no comment on the litigation.

ACQ, MCQ, and treatments such as copper azole compound have largely replaced chromated copper arsenate, which the Environmental Protection Agency banned for residential use in 2004. In 2006, Osmose introduced MCQ, which contains micrometer-sized bits of copper. Before 2006, Osmose licensed ACQ, which contains dissolved copper, from Viance. However, when Osmose introduced MCQ, Viance sued in U.S. District Court for the Southern District of New York, claiming Osmose developed the new preservative with technology from Viance. The trial ended without a decision in 2007, when the dueling firms agreed to withdraw their dispute.

Viance declined to talk with C&EN about its disputes with Osmose. However, before the latest suit was filed on March 3, Viance had plenty to say. Over the course of 2008, the firm posted several references on its website to a study claiming that a yearlong field test of treated wood in Hawaii and Japan showed that MCQ-treated samples decayed while ACQ-treated wood did not.

Two months ago, Viance posted a press release claiming it discovered decayed MCQ-treated wood installed for less than 18 months at several residential subdivisions in the southeastern U.S. Such decay, it said, is “considered unacceptable for providing long-term structural integrity for residential and commercial use.” The decayed wood suggests “alarming consumer safety concerns about structures built using micronized-copper-treated wood,” Viance claimed.

A day after Viance issued the release, Osmose came out swinging. “Viance is once again attempting to create unfounded concerns about consumer safety and product performance, using statistically insignificant and suspect data,” Osmose President Paul A. Goydan said. The bottom line, Osmose claimed, is that Viance is the only copper-based wood preservative maker that does not have micronized technology and so has waged a “desperate campaign” to discredit it.

NOT LONG AFTER, Timber Products Inspection, the testing organization Viance relied on to verify the decay of MCQ-treated residential lumber, issued an open letter noting “certain limitations” in its report for Viance. Timber Products said that although its report provided “a logical basis for additional investigation,” it cautioned readers against making “generalizations that may not be supported by the report.” Timber Products didn’t return C&EN’s calls for comment.

By mid-February, 17 wood pressure treaters, only some of which use MCQ, said they had had enough. “This campaign is either an ill-advised marketing ploy or an inappropriate method for addressing technical concerns,” they wrote in an open letter to Viance Chief Executive Officer Steve Ainscough.

One of the signers, Bumby of Maine Wood Treaters, tells C&EN that he did not use MCQ at the time he signed the letter but that he recently switched to a formulation from Osmose similar to MCQ to treat porous soft woods such as southern and red pine. He says he still uses ACQ for difficult-to-penetrate woods such as eastern hemlock and eastern white pine, indicating there is a place for both treatments in the market.

Still, the dispute dragged on. In early March, when Osmose filed its lawsuit against Viance, it also set up a website,, as a counterbalance to, Viance’s website about alleged MCQ failures. Goydan explained in a statement that Osmose filed the suit “to protect the integrity of our company, the quality of our products, and the credibility of the treated wood industry.”

Three weeks ago, the federal court judge overseeing the Osmose case against Viance issued a temporary injunction that allows Viance to publish its studies but prohibits it from drawing “broad conclusions about the effectiveness of micronized copper preservatives in general.”

The next step in the case will be for the judge to determine what Viance may say in its advertising “in light of the studies available.” He has set a hearing for May 19.



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