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Toyobo resolves suit over defective body armor

Japanese fiber maker to pay U.S. government $66 million for garments that were not bulletproof

by Marc S. Reisch
April 5, 2018 | APPEARED IN VOLUME 96, ISSUE 15

Credit: Shutterstock
The U.S. government claims Toyobo's fiber degraded over time in bulletproof vests.

The Japanese company Toyobo has agreed to pay the U.S. government $66 million to resolve claims that it sold a defective high-performance fiber used in bulletproof vests purchased by federal and state law enforcement agencies.


The agreement settles a 14-year-old lawsuit charging that Toyobo knew its Zylon poly-benzobisoxazole (PBO) bullet-resistant fiber could fail prematurely when subject to body heat and humidity. The suit also claimed that Toyobo didn’t disclose problems when it knew about them and misled both the U.S. government and vest manufacturers.

“Selling material for these vests that one knows to be defective is dishonest, and risks the lives of the men and women who serve to protect us,” said U.S. Attorney General Jeff Sessions in a statement.

Toyobo’s own statement said it settled with the Department of Justice (DOJ) without admitting any legal liability to avoid the uncertainty and cost of a jury trial. The firm argues that it is not at fault and that “every Zylon vest at issue passed the National Institute of Justice’s (NIJ) performance standards for ballistic vests.”

The NIJ, a DOJ research agency, decertified PBO-containing vests in 2005 after it found that 50% of used vests could not stop bullets they had been certified to stop. A 2007 study by another government agency, the National Institute of Standards & Technology, found that PBO yarns lost 30% of their tensile strength after 26 weeks of testing at elevated temperature and moisture.

The decertification and study followed the death of a California police officer and the serious injury of a Pennsylvania officer in 2003. Both wore PBO vests that failed to protect them.

DOJ claims that Toyobo knew in the early 2000s about the PBO complications. It also says the firm generated secret internal reports on the problem and then disseminated misleading information that “understated the degradation data.”

The once-promising PBO fibers were developed as alternatives to aramid fibers in the 1970s at the U.S. Air Force Research Laboratory, according to a National ­Academies Press study. Dow Chemical and the research institute SRI International further developed the fiber. Toyobo then licensed and commercialized PBO in the mid-1990s.

SRI said the fibers could be spun into heat-resistant yarn with a tensile strength that is 1.6 times as high as that of Kevlar, a DuPont p-aramid fiber widely used in body armor. PBO fiber continues to be used in high-strength applications, including tennis rackets and snowmobile drive belts.

To date, DOJ says, it has recovered $132 million in the scandal from Toyobo, vest makers, and others. Still outstanding is a lawsuit against Honeywell International in which the government claims Honeywell supplied bulletproof vest makers with Zylon-laminated material that it knew was defective.



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