LNP Wins a Round in Long-Fiber Patent Case.

After three trials and almost four years, the U.S. District Court in Wilmington, Del., rendered a final judgment in the patent dispute between LNP Engineering Plastics Inc., Exton, Pa., and RTP Co., Winona, Minn. The latest court decision went in LNP's favor, upholding a patent on long-fiber reinforced thermoplastics (LFRT) produced by a melt-pultrusion process. The court also issued a permanent injunction prohibiting RTP from making and selling LFRT products containing 30% or more fiber by volume. Previous decisions determined that RTP could sell LFRT with less than 30% fiber volume.

RTP sources say 90% of its LFRT business is in products with less than 30% fiber by volume. They note polypropylene LFRT may contain up to 53% long glass by weight, and nylon and PPA can have 45% glass by weight, and not exceed 30% by volume.

The long-running legal battle is not yet over. Both LNP and RTP are appealing--LNP to prevent RTP from selling LFRT with less than 30% fiber, and RTP to be free to make LFRT with higher volume percentages of fiber. LNP sources expect the U.S. Circuit Court of Appeals in Washington, D.C., to take about nine months to issue a decision.

In the meantime, RTP has come out with a new family of reinforced thermoplastics that it calls Advanced Fiber Compounds (ADF), which are made by a proprietary modified extrusion compounding process. Because they are not made by melt pultrusion, ADF products are not legally limited in fiber content, RTP says. ADF reportedly provides structural properties similar to those of LFRT but at around 20% lower cost.