Hercules Inc. v. Exxon Corp.

• Decision Date: 29 July 1980
• Docket Number: Civ. A. No. 3439.
• Citation: 497 F. Supp. 661
• Parties: HERCULES INCORPORATED, Plaintiff, v. EXXON CORPORATION, Defendant.
• Court: U.S. District Court — District of Delaware

497 F. Supp. 661

HERCULES INCORPORATED, Plaintiff, v. EXXON CORPORATION, Defendant.

Civ. A. No. 3439.

United States District Court, D. Delaware.

July 29, 1980.

COPYRIGHT MATERIAL OMITTED

David F. Anderson of Potter, Anderson & Corroon, Wilmington, Del., for plaintiff; Caspar C. Schneider, Jr., Stanley L. Amberg, William J. Hone, Richard P. Ferrara, and Deborah A. Brandstater of Davis, Hoxie, Faithfull & Hapgood, New York City, of counsel.

Arthur G. Connolly, Jr. of Connolly, Bove & Lodge, Wilmington, Del., for defendant; Thomas F. Reddy, Jr., Berj A. Terzian, Jonathan A. Marshall, and Ronald A. Bleeker of Pennie & Edmonds, New York City, Lee Chasan of Exxon Chemical Co., of counsel.

OPINION

CALEB M. WRIGHT, Senior District Judge.

In this action, Hercules Incorporated ("Hercules") charges Exxon Corporation ("Exxon")¹ with infringing both literally and under the Doctrine of Equivalents, United States Patent 3,211,709 which covers a form of sulfur-vulcanizable ethylene propylene terpolymers ("EPT's") useful as synthetic rubbers.² Hercules's interest in this patent arises by virtue of an assignment from Great Britain's Dunlop Rubber Company, Ltd. ("Dunlop") whose interest in turn is derived from an assignment by its three employees, Drs. Stephen Adamek, Edward Allen Dudley and Raymond Woodhams ("Adamek et al.") whom the patent lists as inventors. Exxon defends by charging that some, if not all, of the claims of the Adamek et al. patent are invalid because (1) the patent involves an obvious development; (2) its disclosure is inadequate; and (3) it was procured by fraud. It is the opinion of this Court that some of Adamek et al.'s involved claims are invalid because Adamek et al.'s disclosures are inadequate. The remaining involved claims, although valid, are not infringed by Exxon's products.

THE CLAIMED PRODUCTS

Hercules charges Exxon with infringing Adamek et al. patent claims 1-2, 4-7, 10, 13-14 and 16-18³ of which claims 1 and 17 are representative:

1. A sulfur-vulcanizable, elastomeric copolymer of at least two straight chain alpha-olefins of from 2 to 10 carbon atoms and an ethylenically unsaturated bridged-ring hydrocarbon containing at least two ethylenic double bonds, at least one of said double bonds being in one of the rings of the bridged ring present in said hydrocarbon, said hydrocarbon being present in the copolymer in an amount imparting sulfur-vulcanizability, said hydrocarbon having from 7 to 20 carbon atoms, the total straight chain alpha-olefin content of said copolymer being at least 50%.

. . . . .

17. A rubbery copolymer of ethylene consisting of ethylene, at least one alpha-olefin having the structure R-CH = CH2, in which alpha-olefin R is a C1-C8 alkyl radical, and dicyclopentadiene, there being at least about 2.5 to 92.6% ethylene units by weight and at least about 2.5% to about 92.6% of said alpha-olefin units by weight, and, about 2.5 to 50% of dicyclopentadiene units by weight in said copolymer.⁴

Claim 1 (which typifies claims 1-2, 4-7, 10 and 16) and claim 17 (which typifies claims 13-14 and 17-18), thus cover terpolymers containing three hydrocarbons, at least two of which must be alpha-olefins,⁵ including especially ethylene⁶ and propylene.⁷ Adamek et al.'s terpolymers must also contain a bridged-ring polyolefin.⁸ The essential difference between claim 1 and claim 17 is that while claim 1 broadly specifies the use of a large group of bridged ring polyolefins, claim 17 narrowly specifies the use of only one dicyclopentadiene ("DCP").⁹

During polymerization, at least one double bond from each olefin becomes a single bond, releasing two electrons-one to each previously doubly bonded carbon atom. These electrons form the single bonds through which the two previously doubly bonded carbon atoms become incorporated within the main chain of the polymer. Ethylene, for instance, polymerizes in this fashion, known as "head-to-tail" or "1,2-" addition:¹⁰

Bridged-ring polyolefins are added to the polymer in order to make it curable. Curing refers to a treatment by which rubber is stiffened from a putty-like compound into a harder more resilient and useful material:

Molecules . . . in a piece of .. unvulcanized, rubber . . . exist in a randomly coiled arrangement. If that article is stretched . . . the randomly coiled molecules extend in the direction of stress. . . . and the main chain of the molecules tend to align in the direction of the stress. . . . If you immediately release the article, the molecules will then return to their randomly coiled shape in their original position and the molecule will resume its original shape. . . . If, however, you stress an uncured sample of rubber for a long enough time . . . the main chain of the molecules will flow past one another This is known as creep¹¹ .. And now when you release the stress on that article, it will no longer retract to its original shape. It will have deformed into its new shape.

In contrast, if you can cross-link or cure the polymer, ... and .. stress the molecules by stretching the assembly, again the molecules will tend to stretch out in the direction of the stress. ... Now, however, the main chain of the molecules are tied together in a three-dimensional network by the cross-links. They can no longer flow past one another because they're tied together. ... The molecules remain in the stressed condition for as long as you hold it stressed. When you release it, they want to go back to their original randomly coiled arrangement, and that takes the assembly back to its original shape. ...¹²

Curing is successful when it significantly increases a polymer's stiffness or resistance to stretching. Stiffness is measured by hanging weights from a molded ring of polymeric material and measuring the resulting elongation.¹³

Curing is usually accomplished by incorporating cross-links of sulfur. Sulfur curing requires the presence of double bonds, which the curing process converts to single bonds. Hence, the need for using polyolefins which, by definition, contain at least two double bonds. The theory is that a polyolefin will sacrifice one of its double bonds for polymerization. The remaining double bonds will remain, providing sites for sulfur vulcanization.¹⁴

THE ACCUSED PATENT

During World War II, Japan cut off the Allies' traditional sources of natural rubber.¹⁵ This caused a massive Allied research program to develop a synthetic substitute.¹⁶ For reasons of security, this program was centered among the American rubber companies;¹⁷ as a result, American rubber makers developed their technology far in advance of their foreign counterparts, including Dunlop.¹⁸ In its subsequent efforts to catch up with the American technology, Dunlop established the North American Research Center ("N.A.R. C.") in Toronto, Canada about 1950.¹⁹ About 1954, N.A.R.C. hired Drs. Raymond Woodhams, Stephen Adamek and Edward Allan Dudley,²⁰ who together set out to make the invention involved in this suit.

Adamek, Dudley and Woodhams began their work during the fall of 1956, when they homopolymerized several olefins. They also copolymerized ethylene and propylene,²¹ and soon they began searching for a suitable diene to polymerize with ethylene and propylene.²² They initially investigated isoprene and butadiene, but when this research proved unfruitful, they considered other dienes including DCP.²³

The idea of using DCP may have originated with Dudley, who remembered that in June, 1956, Enjay advertised "that DCP was available and that Enjay would be interested in people finding some use for it. . . . It struck Dudley as an interesting possibility as a diene ... so he wrote away and asked for . . . samples."²⁴

The idea of using bridged ring structures such as DCP may also have originated with Woodhams who attended a September, 1956 meeting of the American Chemical Society in Atlantic City, New Jersey, where he listened to a lecture by three E. I. du Pont de Nemours & Company ("Du Pont") employees discussing the preparation of homopolymers of norbornene.²⁵ Woodhams thought that norbornene, which closely resembles DCP's bridged-ring,²⁶ "would be a useful monomer to incorporate in our screening program."²⁷

On April 26, 1957, Adamek et al. began preparing and testing EPT's containing numerous third monomer candidates including two bridged-ring dienes-DCP and norbornadiene²⁸ — and a variety of other compounds.²⁹ Only those experiments with the bridged-ring dienes proved successful.³⁰

Adamek et al. then prepared a "rough draft for patent application"³¹ which they sent on June 12, 1957 to Dunlop's Patent Department in Birmingham, England.³² From this draft, Dunlop's Patent Department prepared a patent application and filed it in Great Britain on July 17, 1957.³³ On July 14, 1958, Adamek et al. filed an American application,³⁴ claiming the benefit of their British filing date under 35 U.S.C. § 119.

The American Patent Examiners initially rejected all of Adamek et al.'s claims.³⁵ Dunlop attempted to meet these objections,³⁶ but was unable to do so³⁷ prior to its November 30, 1961 assignment of the Adamek et al.'s American rights to Hercules.³⁸ Hercules's Edwin H. Dafter then assumed responsibility for Adamek et al.'s application. Dafter immediately cancelled all claims then on file and submitted a new set.³⁹ At about the same time, Dafter copied claims from and requested an interference⁴⁰ with U.S. Patent 3,000,866, which had previously issued, on September 19, 1961, to Du Pont's Robert Edward Tarney.⁴¹ The Patent Office granted this request⁴² and Hercules's interference expert Clinton F. Miller⁴³ assumed responsibility for its prosecution.⁴⁴ On or about July 16, 1964, the interference terminated in favor of Adamek et al.⁴⁵ Adamek et al.'s patent eventually issued on October 12, 1965.⁴⁶

THE LITIGATION

During Hercules's prosecution of Adamek et al.'s application, Exxon began making EPT's⁴⁷ containing methylene norbornene ("MNB")⁴⁸ and ethylidene...