810 F.2d 1148 (Fed. Cir. 1987), 86-1327, N.V. Akzo v. E.I. Dupont de Nemours

Docket Nº:Appeal Nos. 86-1327, 86-1358.
Citation:810 F.2d 1148
Party Name:1 U.S.P.Q.2d 1704 N.V. AKZO, Aramide Maatschappij v.o.f., Appellant/Cross-Appellee, v. E.I. DUPONT de NEMOURS, Appellee/Cross-Appellant.
Case Date:February 05, 1987
Court:United States Courts of Appeals, Court of Appeals for the Federal Circuit

Page 1148

810 F.2d 1148 (Fed. Cir. 1987)

1 U.S.P.Q.2d 1704

N.V. AKZO, Aramide Maatschappij v.o.f., Appellant/Cross-Appellee,


E.I. DUPONT de NEMOURS, Appellee/Cross-Appellant.

Appeal Nos. 86-1327, 86-1358.

United States Court of Appeals, Federal Circuit

February 5, 1987

C. Frederick Leydig, Leydig, Voit & Mayer, Ltd., Chicago, Ill., argued for appellant/cross-appellee. With him on the brief were Charles S. Oslakovic, John Kilyk, Jr., Norval B. Galloway and Robert F. Green, Leydig, Voit & Mayer, Ltd., of counsel. Also on the brief were Denis McInerney and P. Kevin Castel, Cahill, Gordon & Reindel, New York City and Robert H. Falk, Hubbard, Thurman, Turner & Tucker, of Dallas, Tex.

Joseph Fitzpatrick, Fitzpatrick, Cella, Harper & Scinto, New York City, argued for appellee/cross-appellant. With him on the brief were John A. O'Brien, Henry J. Renk, Charles P. Baker, Laura A. Bauer and Bruce C. Haas. Also on the brief were Robert H. Patterson, Jr. and Anne Marie Whittenmore, McGuire, Woods & Battle, Richmond, Va. and Robert C. Kline, E.I. DuPont de Nemours, Wilmington, Del.

Before MARKEY, Chief Judge, DAVIS and NIES, Circuit Judges.

DAVIS, Circuit Judge.

Akzo N.V. and Aramide Maatschappij v.o.f. (Akzo) brought suit against E.I. Du-Pont de Nemours & Co. (Du Pont) in the

Page 1149

United States District Court for the Eastern District of Virginia alleging that Du Pont had deliberately infringed U.S. Patent No. 4,308,374 ('374 patent) issued to Akzo. Akzo sought an injunction prohibiting Du Pont from infringing the '374 patent, an accounting for past damages, a determination that Du Pont's alleged infringement was willful, and an award of attorney fees. Du Pont counterclaimed, asserting that the '374 patent was invalid under 35 U.S.C. Sec. 103; Du Pont also asserted that Akzo had engaged in inequitable conduct before the Patent and Trademark Office (PTO). The District Court, in a detailed and well-reasoned opinion, held the '374 patent invalid under 35 U.S.C. Sec. 103 and therefore not infringed, but concluded that Akzo had not engaged in inequitable conduct before the PTO. Akzo v. E.I. du Pont de Nemours, 635 F.Supp. 1336, 230 USPQ 263 (E.D.Va.1986). We affirm.



Du Pont and Akzo have both been involved in the commercial manufacture of high-strength, low-density synthetic aramid fibers from poly-p-phenyleneterephthalamide (PPD-T). 2 See Akzo N.V., Enka B.V., Aramide Maatschappij v.o.f., and Akzona Inc. v. U.S. International Trade Commission and E.I. duPont de Nemours & Co., 808 F.2d 1471 (Fed.Cir.1986). These fibers have a number of commercial applications including roping, tires, aviation parts, bullet-proof clothing, and boat hulls. In order to produce a synthetic fiber with high tensile strength, high viscosity solutions of PPD-T must be prepared. The synthetic fibers are then spun from these high viscosity solutions. The patent at issue--Akzo's '374 patent--describes a process for a solvent system whereby PPD-T having an inherent viscosity 3 of at least 2.5 can be made by using N-methylpyrrolidone (NMP) containing at least 5% by weight calcium chloride (CaCl2 ) salt.

In the mid-1950's, Du Pont began research on aromatic polyamides with the aim of producing a high-tensile strength synthetic fiber. In order to spin a satisfactory fiber, the aromatic polyamides must first be dissolved in a suitable medium. In 1957, Du Pont conducted research on a number of polymerization solvent systems including NMP combined with inorganic salts such as lithium chloride (LiCl) and CaCl2 . In 1969, Du Pont targeted PPD-T as the polymer of choice to produce a high-strength synthetic fiber. Researchers investigated a number of polymerization solvent systems for use with PPD-T, but in 1971 Du Pont elected to use hexamethylphosphoramide (HMPA) as a solvent system to yield PPD-T with the high inherent viscosity required for spinning into a finished fiber. Du Pont immediately discontinued research into alternative solvent systems. There were, however, problems with the HMPA solvent system. Du Pont was aware that HMPA was toxic to humans, and in 1975 discovered that it could be carcinogenic to animals. Upon discovering the possible carcinogenic effect, Du Pont began in September 1975 to research again into possible alternative solvent systems. Akzo scientists informed researchers at Du Pont that they had been able to produce a high inherent viscosity PPD-T fiber without using HMPA as a solvent, but did not specify the alternative solvent system. 4 Prior to 1975, Du Pont had not used NMP in the polymerization of PPD-T, but in 1969 it had used NMP with LiCl in the polymerization of another fiber, 1,4 poly-p-benzamide (Fiber B). In addition, in 1969-70, Du Pont had been able to make a third fiber, chloro-PPD-T, using dimethylacetamide (DMAc) or NMP as the polymerization

Page 1150

medium in combination with LiCl or CaCl2 , but achieving much better results with LiCl.

Early work on an alternative polymerization solvent system by Beers, Katz, and Miller of Du Pont included experimentation with NMP with various salts. It was well-known in the...

To continue reading